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The Colorado Potato Beetle 



Insects Injurious 
to Vegetables 



By 

F. H. CHITTENDEN, SC. D. 

United States Department of Agriculture 



ILLUSTRATED 



NEW YORK 

ORANGE JUDD COMPANY 

LONDON 

KEGAN PAUL, TRENCH, TRUBNER & CO., Limited 

1907 



LIBRARY of COWGRPSS 
Two Coole? Received 

OCT ii isor 

Cooyriffht Entry 
A up fc ffc7 



CLA 



XXc,, NOi 



COPY B/ 



Copyright 1907 

BY 
ORANGE JUDD COMPANY 

y4// Rights Reserved 



Entered at Stationers' Hall 
I,ondon, England 



PREFACE 

Among the hordes of insect foes with which the American 
farmer has to deal, those affecting vegetable crops are in many- 
respects most troublesome. Vegetable plants are exceptionally 
perishable, and the control of their insect enemies entails a 
very considerable expenditure of money and time. The an- 
nual losses due to insect attack on vegetable crops is esti- 
mated at 20 per cent., or double that of the average farm crop. 
The injurious vegetable-feeding forms outnumber in species the 
insect enemies of any other single class of crops, excepting 
possibly deciduous fruits, and this nearly endless variety of 
pests necessitates information in regard to each. Many are 
intermittent in attack, hence the grower should be forewarned 
in order to guard against injury or to check it before irrep- 
arable damage has been accomplished. The progressive veg- 
etable grower should be as amply equipped with knowledge 
as the fruit grower, and if he would be entirely successful in 
avoiding losses from insect ravages he should be provided with 
a complete outfit for spraying operations and should keep on 
hand or know where to obtain at short notice a good supply 
of necessary insecticides. The more general observance of 
certain farming methods with a view to the prevention of in- 
sect injury will greatly lessen the losses from this source. 
Until within recent years few farmers in planning the manage- 
ment of the farm for the season considered the effect which 
any given method of tillage would have upon injurious insects. 
Too frequently they fail to look far ahead, and as a rule ro- 
tation of crops where practiced is more for the sake of soil 
improvement than for the avoidance of insect injury, and yet 
crop rotation is the best and sometimes the only remedy for 



VI PREFACE 

certain species of insects. Among other general methods of 
farming strict cleanliness, including the destruction of weeds 
and burning over fields after harvest, fall plowing, crop ro- 
tation, the use of fertilizers, and the selection of the proper 
place and time for planting, must be considered. A knowledge 
of the classification of insects sufficient to enable the farmer 
to distinguish friends from foes is valuable, and finally comes 
a knowledge of what insecticides and repellents to use and 
the best means of preparing and applying them. 

Accounts of most of our noxious species of insects have been 
published. These accounts, however, are distributed through 
government and state publications, reports of agricultural so- 
cieties, magazines, and periodical publications of entomological 
societies, and even the daily press. As an example of the 
number of such publications on American economic ento- 
mology, the Bureau of Entomology, United States Department 
of Agriculture, has cited no less than 12,645 titles that had 
appeared to January 1, 1905, and the number of references to 
noxious insects is about 72,000. The average farmer has 
neither time nor opportunity to consult a tithe of these 12,- 
000 odd works, and it is therefore the object of the follow- 
ing pages to collate concise accounts of the principal insects 
which affect one class of crops — vegetables. The order which 
will be followed is, as far as practicable; alphabetical, begin- 
ning with the insect enemies of asparagus, and ending with 
those which affect sweet potato, and finally miscellaneous or 
unclassified crops. 

The insect enemies of vegetables have not hitherto been con- 
sidered as a special topic in comprehensive form. Separate 
accounts, however, on the economic entomology of certain 
vegetables have been published, for example, of beets and of 
sweet potato. 

In presenting this work to the public its author does not 
claim originality for its contents. It is, however, largely com- 



PREFACE Vil 

piled from his own writings, although it has been found 
necessary to draw also from the works of others, and is based 
on an experience of about ten years with the subject with 
which it deals. The illustrations are in large part the same, or 
adaptations of, figures previously used in the Bureau of En- 
tomology, United States Department of Agriculture, and are so 
credited. 

F. H. Chittenden. 
United States Department of Agriculture, 
September, ipo/. 



CONTENTS 



PAGE 

Preface . . . v-vii 

Introduction . . . x-xiv 

1 CHAPTER I 

Value of a Knowledge of Entomology .... 1-15 
General considerations — Classification of insects — 
Orders of insects — Natural elements in the control 
of insects. 

CHAPTER II 

Prevention by Farming Methods . . . . _ . 16-25 

Selection of place and time for planting — The main- 
tenance of vigorous growth — Burning over fields 
and waste lands — Crop rotation — Diversified agri- 
culture — Fall plowing and cultivating — Clean farm- 
ing methods — Farm inspection — Cooperation in the 
control of insects. 

CHAPTER III 

Mechanical Methods of Destroying Insects or Prevent- 
ing Injury 26-29 

CHAPTER IV 

Insecticides and Their Uses _ _ 30-48 

Stomach poisons, arsenicals, etc. — Contact poisons 
— Insecticides which kill by suffocation — Proprie- 
tary insecticides — Insecticide apparatus — Remarks 
on applying insecticides. 

CHAPTER V 

General Crop Pests 49~9i 

Cutworms and related insects — Miscellaneous cater- 
pillars — Leaf-beetles — Flea-beetles — Blister beetles — 
Grasshoppers and related insects — White grubs — 
Wireworms — Aphides, plant-bugs and related insects 
— The red spider. 

CHAPTER VI 

Insects Injurious to Asparagus . 93-98 

viii 



CONTENTS IX 

CHAPTER VII page 

Insects Injurious to Beans and Peas . 99-H9 

CHAPTER VIII 
Insects Injurious to Beets and Spinach „ . . 120-130 

CHAPTER IX 

Insects Injurious to Cabbage and Other Cruciferous 

Crops . . . ■■•.'• • •■ • • 131-154 

CHAPTER X 

Insects Injurious to Cucumber, Melon and Related 

Plants 155-175 

CHAPTER XI 

Insects Injurious to Celery, Parsnips and Related 

Plants 176-188 

CHAPTER XII 
Insects Injurious to Sweet Corn . . . . . 189-212 

CHAPTER XIII 
Insects Injurious to Potato and Similar Vegetables . 213-228 

CHAPTER XIV 
Insects Injurious to the Tomato 229-234 

CHAPTER XV 
Insects Infesting the Sweet Potato .... 235-243 

CHAPTER XVI 

Insects Injurious to Miscellaneous Vegetable Crops . 244-251 
The onion and other bulb crops — Rhubarb — Let- 
tuce — Okra or gumbo — Salsify — Pepper. 



CHAPTER XVII 

Bibliography . 252-258 

Index . . . 259-262 



INTRODUCTION 



Vegetables are subject to attack by insects from the time 
the seed is planted until the edible portion is ready for cooking. 
Insect injury manifests itself in different ways according to 
the plant attacked, the insect concerned, the stage of the insect, 
and the age and condition of the plant. 

Manifestations of Insect Injury. — If plants soon after the 
seed has been sown fail to appear in due time, such failure is 
apt to be attributed to unfavorable atmospheric 
conditions or to imperfect seed, but examination 
will frequently show that some insect is at work. 
Among insects destructive to planted seed are 
wireworms and root-maggots, and in some cases 
insects that have fed on the seed stock while in 
store are planted with the seed, and this they 
destroy by eating out the germ. Familiar ex- 
amples are the bean and pea weevils. 

Asparagus tips when ready for cutting are 

ruined for market by the asparagus beetles (see 

Fig. l— Aspara- **£• I ) * ^ plants like tomato that are reset are 

gus tip, showing cut off abruptly near the ground, cutworms are 

by asparagus near ty always at work. If the minute leaves of 

beetles. (Au- plants like cucumber, soon after beginning to 

thor's illustra- . , • i i 

tion, u.s.Dept. sprout, are found eaten away, causing the plants 
A § r) to die, cucumber beetles are present. Corn is 

similarly affected by flea-beetles, as are also potato and other 
vegetables. 

When stems or stalks of various plants are found with one 
or more holes of varying size, from that of a straw to con- 
siderably larger, this is evidence of a borer within, particularly 




INTRODUCTION 



XI 



if excrement is exuding. Common species which do this in- 
jury are the common and corn stalk-borers and the grass- worm. 
When plants like corn make unequal starts, a hill here and 
there showing greater thrift than elsewhere, injury is apt to 
be due to root-aphides. As a rule, these insects are ac- 
companied by ants, which in most cases foster the "lice," and 
sometimes feed on the seeds. 

When the leaves of plants are seen to be withering, and 
aphides or other sucking insects cannot be de- 
tected above ground, search will usually reveal 
the presence of white grubs, wireworms or other 
insects working below the surface, and the same 
is true of corn plants that fall after windstorms, 
root-worms also being present at such times. 
Another manifestation of the presence of root- 
worms is in the plants requiring too long a time 
for maturing, and producing sterile stalks, and, 
in the case of corn, yielding nubbins instead of 

complete ears. 
When young 
leaves are 
found with 
small round 
holes of about 
the size of a 
pea or a little 
smaller, leaf- 




Fig. 2.— Bollworm entering bean pod, Somewhat enlarged 
(Authors illustration, U. S. Dept. Agr.) 



beetles are usually present, while much smaller holes occurring 
in great profusion over leaves usually betoken the presence of 
flea-beetles. Extremely large and irregular holes in leaves of 
older growth are made by grasshoppers, crickets, and the larger 
caterpillars such as "woolly bears." 

Fruits such as melons are attacked by the melon worm and 
pickle worm; tomato, beans and corn by the bollworm, tomato 



Xll INTRODUCTION 

fruit worm or ear worm (fig. 2), and the edible roots of 
such plants as beet and carrot, are subject to injury by the 
carrot beetle, while potato tubers are damaged by the potato 
tuber worm. Seed pods and similar coverings of seeds are 
attacked by numerous insects, such as the corn ear worm, cu- 
cumber beetles, and others. Growing seeds are liable to be 
injured by some of the last mentioned insects as well as by some 
others which begin development when the seed approaches ma- 
turity. Familiar forms are the bean and pea weevils, and the 
Angoumois grain moth. 

Many other forms of injury might be cited, but it may suffice 
to briefly mention the curling and dying down of leaves like 
melon, due to the presence of the melon aphis; the wilting and 
dying of squash caused by the severance of the stalks by the 
vine borer feeding within; the discoloration of leaves such as 
radish and their subsequent drying, owing to leaf-miner attack; 
and the destruction of whole plants of various kinds by army 
worms and migratory cutworms. 

Every year that passes brings with it some new entomolog- 
ical problem to be solved, and this is especially true of insect 
injury to vegetables. The cause is usually a general or local 
outbreak of one or more serious pests, and the species concerned 
may be an old and well-known injurious form; it may be a com- 
paratively unknown species or one that has not hitherto been 
identified with injury to useful plants; again the habits of the 
species may never have been studied owing to previous scar- 
city. It has perhaps lived in obscurity since time immemorial 
before any considerable outbreak attracts attention. It may be 
new to our country or even new to science. 

Determination of the Injurious Insect. — The first problem 
that confronts the grower whose crops suffer from insect in- 
jury is the identification of the insect. Most insects have 
popular names, more or less local, which may be apt or may be 
rank misnomers, conveying no definite meaning. 



INTRODUCTION 



Xlll 



Thus if a southern farmer complain of "the budworm," 
failing to state what plant is being injured, it is an impossi- 
bility to identify the insect concerned. The budworm of corn 
is the twelve-spotted cucumber beetle of the northern states, 
while the budworm of tobacco is the same as the tomato fruit 
worm and the corn ear worm or bollworm or a related species. 

The first pest is Diabrotica 12-punctata; the second is 




Fig. 3.— Diabrotica 12- 
punctata. (Riley, U. S. 
Dept. Agr.) 




Fig. 4.— Bollworm moth in natural position. 
About twice natural size. (Quaintance, 
U.S. Dept. Agr.) 



Heliothis obsoleta. 1 The parent of the first is a beetle (fig. 3) 
and of the latter a moth (fig. 4)-. It should be added that the 
first named species is also known as drill worm, while the latter 
is also called the shatter worm, this last name being shared also 
by the larger corn stalk-borer and perhaps by other species hav- 
ing the same habits, such as the fall army worm. The last is 
the grass-worm of the South and the fall army worm of the 



1 It is to be regretted that the scientific names are not more stable, but the 
bollworm was generally recognized under the name of Heliothis, until it was 
recently changed to H. obsoleta. 



XIV INTRODUCTION 

North. It is the "alfalfa worm" of Kansas and Nebraska and 
elsewhere it is simply called the army worm. Its technical 
name is Laphygma frugiperda. 

It will thus be seen from the examples cited that the popular 
name of an insect has frequently little bearing on its identity. 
The scientific name must be determined. 

A frequent source of injury to plants is due to contiguous 
growers who raise the same, or similar crops, for different pur- 
poses, e. g., some may raise cucumbers for pickling, and in 
the immediate vicinity others grow melons for fruit, so that 
pickle-growers pick their crops while quite young, and the 
fruit-growers when older. This means that after the pickle- 
grower has stopped pickling, numerous vines remain, and the 
insects scatter from them to melon fields. 



Insects Injurious to Vegetables 



CHAPTER I 

VALUE OF A KNOWLEDGE OF ENTOMOLOGY 

GENERAL CONSIDERATIONS 

For an intelligent understanding of the subject of insect 
control by agricultural practice one must know not alone that 
certain conditions produce an increase or decrease of certain 
forms of insects, but how this is accomplished, why the alter- 
nation of one crop with another is apt to result in insect 
injury, and why a system of crop rotation that would be of 
value in the control of one class of insects might be ineffective 
against another; how fall plowing, though destructive to one 
species, would not affect a different insect, and so on. In 
short, a knowledge of economic entomology beyond the fact 
that arsenicals are the proper remedies for mandibulate or 
chewing insects, and that kerosene will kill aphides or plant- 
lice, scale insects, and other soft-bodied insects, is a prereq- 
uisite to intelligent effort in the control of noxious insects. 
Before we can hope to avert losses we must know what our 
insect enemies are, what species are destroying each crop, 
which ones are responsible for primary injury, which are sec- 
ondary or merely auxiliary, how injury is accomplished, when 
injury begins each year, when it ends, as well as other facts. 

Similarly desirable is it to be able to recognize useful in- 
sects, such as ladybirds, syrphus flies, tachina and ichneumon 
flies and other parasites, that these may not be unnecessarily 
destroyed, but, if possible, encouraged in their useful work. 

i 



2 INSECTS INJURIOUS TO VEGETABLES 

The different stages of some insects are so diverse that they 
can be identified only by specialists, and many entomologists 
are unable to recognize them without reference to technical 
descriptions and illustrations. Some knowledge of the distri- 
bution and origin of a species is of value, as well as some 
acquaintance with its history and literature. 

A knowledge of the life history of an insect consists in 
knowing : when, where and how its eggs are deposited ; how the 
larva feeds, and how many stages there are in this period; the 
habits of the larva, whether diurnal or nocturnal, whether 
omnivorous or a dainty feeder; how and where it transforms 
to pupa; how and where and in what stage it passes the 
winter; the number of generations produced each year; the 
first appearance of the insect and its disappearance, and the 
same of each generation; its food plants, natural and culti- 
vated, and above all, its favorite foods, both as larva and adult. 
If to this we add a knowledge of the effect of farm practice 
and of insecticidal and mechanical methods on the insect we 
have, in a general manner, the main facts desired. 

We must determine in what stage and at what time the 
insect is most vulnerable, and by practice and experiment 
learn the best remedy. A knowledge of the appearance and 
place of deposition of the eggs will, in the case of some 
species, furnish means for their control, for many insects can 
be combatted successfully merely by destroying the eggs. 
Others may be killed in their cocoons. 

The most valuable weapon that can be used in combatting 
an insect consists in an intimate knowledge of the insect itself 
and its life economy, its natural enemies, its susceptibility to 
natural influences, heat and cold, dryness and moisture, and 
their effect upon its increase or decrease directly, or indirectly 
by destroying or favoring the growth of its enemies. A 
knowledge of the weeds and wild plants that furnish food for 
these insects, in addition to cultivated plants, and the soils in 



VALUE OF A KNOWLEDGE OF ENTOMOLOGY 3 

which they attain their greatest development is also desirable. 
To this we must add a knowledge of the effects of different 
farm practices upon the insects, as well as of insecticides, 
There are many insects with which we cannot cope by the use 
of poisons, and it is only by a thorough knowledge of their life 
economy from the time the eggs are deposited until the perfect 
insect emerges, that we are able to mitigate losses from their 
ravages. The knowledge of some one or more facts appar- 
ently trivial in themselves may frequently enable us to pre- 
vent by farming methods injury which we cannot cure by 
means of poisons, mechanical or other direct methods 

After seed has been selected with reference to its adapta- 
bility to the soil and climatic and other conditions one of the 
next problems that confront the grower is how to protect the 
crop from noxious insects and diseases. Fortunately we know 
approximately the life history and habits of a large proportion 
of the injurious insect inhabitants of this country, with the 
exception of some few species which have only been recently 
associated with injury, or which have lately been introduced 
from abroad. 

As a necessary preliminary to the discussion of the insect 
enemies of the various vegetable crops, some idea of the struc- 
ture and classification of insects must be given. It is perti- 
nent to follow as a matter of course with general methods of 
control, which include (1) mechanical methods, (2) farm prac- 
tice as preventives and (3) the preparation and means of 
applying poisons for the destruction of insects. Following 
this the different groups of insects which affect various crops 
and are not attached to single crops will be considered. 

CLASSIFICATION OF INSECTS 

If we would have an intelligent understanding of the causes 
that have led to the destruction of our crops, we must know 
something of the classification of insects and their nearest rel- 



INSECTS INJURIOUS TO VEGETABLES 



atives in order that we may be able to distinguish friends 
from foes and true insects from related forms. It is, of 
course, not essential that all of the Latin names which insects 
bear should be memorized, nor that anything approaching a 
complete classification be studied. The object of what is here 
presented on this topic is to assist in the ready identification by 
orders of such creatures as may come under observation as 
enemies or suspected enemies to plants under cultivation. 

It is first desirable to eliminate animals which are not true 
insects but are related to them. These are all included (with 

true insects) under the branch 
Arthropoda of the Animal King- 
dom and are distinguished by 
having their bodies composed of 
rings or segments more or less 
similar, joined together, most of 
them bearing jointed legs, the last 
character separating them from 
earthworms, eel-worms, or hair- 
worms, which have many segments 
but no legs. This branch is di- 
vided into four classes: 

Crustacea (Crabs, lobsters, 
shrimps, crawfish, and sow-bugs 
[Oniscidce]). — Of this class only the sow-bugs or pill-bugs are 
apt to be confused with insects, and are of some economic 
importance, though not so injurious as many suppose. A 
common injurious species is shown in figure 5. 

Arachnida (Scorpions, daddy long-legs, spiders, mites, etc.) . — 
The scorpions are well known in the South and need no de- 
scription. The same is true of the daddy long-legs or harvest- 
men, and spiders are everywhere. Among the mites, however, 
we have one species, the so-called red spider, which is quite in- 
jurious at times and which as it is commonly supposed to be 
an insect we will treat in one of the following chapters. 




Fig. 5.— Water-cress sowbug (Man- 
casellus brachyurus). Enlarged. 
(After Richardson.) 



VALUE OF A KNOWLEDGE OF ENTOMOLOGY 5 

Myriopoda (Thousand-legged worms). — These creatures are 
known to most persons, and are divided into two orders: The 
Centipedes constitute a group in which each segment bears 
only a single pair of legs, while the body is generally flattened, 
and the antennae are long with many joints. They live mostly 
by preying upon other insects. The Millipedes (fig. 6) have two 




Fig. 6.— Myriopod. Enlarged 

pairs of legs to each segment except the first three; the body is 
more or less cylindrical, and the antennae are shorter with few 
joints. Most species feed upon decomposing vegetable matter, 
but some attack growing plants, more particularly those of 
the garden and greenhouse. Injury by these creatures, how- 
ever, is frequently exaggerated, as in the case of the sow- 
bugs, previously mentioned. 

Hexapoda (Insects). — This brings us to the true insects 
which are distinguished from the other three classes that have 
been mentioned by having the 
body divided into three distinct 
portions, — head, thorax (chest), 
and abdomen (belly) (fig. 7). 
They have a single pair of an- 
tennae or feelers, normally three 
pairs of legs, and in the mature 
stage, one or two pairs of wings 
(save in exceptional cases). In 

, , ,. Fig. l.—Polistes bellicosus. Somewhat 

our present advanced state of enlarged . (Marx del, u. S. De P t. Agr.) 
knowledge of the classification 

of true insects they have been divided into no less than nine- 
teen 1 orders, but for present purposes what is known as the 

1 For a list of these orders the reader is referred to pp. 77-81 of Comstock's 
Manual for the Study of Insects, Comstock Publishing Co., Ithaca, N. Y. 




6 INSECTS INJURIOUS TO VEGETABLES 

old Linnsean classification will suffice. This embraces seven 
orders, — Coleoptera, Orthoptera, Lepidoptera, Hymenoptera, 
Neuroptera, Diptera, and Hemiptera. The first six of these 
orders are mandibulate or chewing insects, at least in the most 
active stage of the insect, while the last are haustellate or 
sucking insects. This is important to know as on this classifica- 
tion depends the question as to whether stomach poisons, such 
as the arsenicals, or contact poisons, such as kerosene and its 
different preparations, are best suited for their destruction. 

ORDERS OF INSECTS 

Coleoptera or Beetles. — Beetles are distinguished by having 
a pair of more or less horny elytra or wing-covers which nor- 




Fig. 8.— Convergent ladybird (Hippodamia convergens) . a Adult; b, pupa, 
c, larva. All much enlarged. (Author s illustration, U. S. Dept Agr ) 



mally meet in a straight line down the back. Beneath them 
are the true membranous wings, usually folded. The mouth- 
parts of beetles and their larvae (the latter usually called 
grubs) are formed for biting. A common beetle, a beneficial 
ladybird, is shown in figure 8, in different stages. Many species 
of beetles are injurious both in the adult and larval stages.. 
Among the best known forms of this order that injuriously 



VALUE OF A KNOWLEDGE OF ENTOMOLOGY 7 

affect vegetables are wireworms, white grubs and their parents 
the May and June beetles, leaf-beetles, flea-beetles, pea and 
bean weevils, blister beetles, bill-bugs and other snout-beetles. 
Lepidoptera (Butterflies and moths). — This order consists of 
insects having four membranous wings covered with more or 
less minute overlapping scales. The mouth-parts of the 
adults are formed for sucking, but the larvae (called eater- 




Fig. 9.— Cabbage looper (Autographa brassicse). a, Male moth: b, egg; c, 
caterpillar; d, pupa in cocoon, a, c, d. One-third larger than natural; b, more 
enlarged, (a, c, d, after Howard; b, Chittenden, U. S. Dept. Agr.) 



pillars, "worms," etc.) have well-developed chewing mouths. 
The Lepidoptera are of about equal importance with the 
Coleoptera or beetles as pests. 

Examples of noxious forms that are destructive to vegetable 
crops are found in the cutworms, army worms, webworms, 
cabbage and tomato worms and various caterpillars. The cab- 
bage looper is shown in figure 9 in its four principal stages. 



8 



INSECTS INJURIOUS TO VEGETABLES 



Hymenoptera {Saw flies, ants, wasps, bees, etc.). — In this order 
there are two pairs of membranous wings with comparatively 
few veins, the hind-wings being the smaller pair. The mouth- 
parts of the adults are formed for both biting and sucking, 
and those of the larvae, which are injurious, for biting. The 
females are furnished with stings, piercers or saws. In this 
order there are comparatively few noxious forms, and most 
of these are confined to the sawflies whose larvae, known as 
slugs and false-worms, consume vegetation, doing injury similar 




Fig. 1 0.— Screw-worm (Compsomyia macellaria). a. Maggot; b, head of 
same; c, anal segment from rear; d, puparium; e, adult fly;/, head from 
side. All enlarged. 

to that accomplished by caterpillars. Some species of ants 
are troublesome, both directly and indirectly, in the latter 
case by acting as carriers of aphides or plant-lice, scales, and 
some other insects. This order, however, contains many bene- 
ficial forms, such as ichneumon and chalcis flies — parasites of 
noxious insects, and wasps which also destroy insect pests. 
One of these is shown in figure 7. 

Diptera, or Flies. — Insects of this order have a single pair 
of wings which are borne on the mesothorax or middle por- 
tion of the thorax. The metathorax or hind portion bears a 
pair of knobbed thread-like processes called halteres, poisers, 
or balancers. The mouth-parts are formed for sucking in the 
adult condition, but in the larvae (called maggots) the mouth- 



VALUE OF A KNOWLEDGE OF ENTOMOLOGY 



parts are for biting. To the Diptera belong such pernicious 
insects as mosquitoes, house and horse flies, and root-maggots. 
For illustrations of the Diptera, see figures io«and 20. 
Orthoptera (Grasshoppers, crickets, roaches, katydids, etc.). 
— In this order the insects have two pairs of wings, — the first 
somewhat horny and overlapping when at rest, the second 
pair thin and folded when at rest in plaits like a fan. The 
metamorphosis is incomplete, and all forms of the insect (ex- 
cept the egg) are active, with biting mouth-parts. The Rocky 
Mountain locust is an example of this order (figs, n and 12). 
Hemiptera. — This order divides into three suborders, — the 
Heteroptera or true bugs, the Homoptera containing aphides, 
leafhoppers, etc., and the Physopoda or thrips. These groups 

have in common four wings, 
the mouth-parts in all stages 
ss?4ifeL JFBC — formed for sucking, with in- 

complete metamorphoses. 




Fig. 11. — Rocky Mountain locust 
(Melanoplus spretus). a, a, Newly- 
hatched nymph; b, full-grown nymph; 
c, pupa, natural size. (After Riley.) 




Fig. 1 2.— Rocky Mountain locust (Melan- 
oplus spretus). Adult. Natural size. 
(After Riley.) 



Suborder Heteroptera. — In the true bugs the anterior wings 
are thickened at the base and thinner at the extremities and 
overlap on the back, and the beak arises from the anterior 
portion of the head. It includes various forms of noxious 
insects, such as the chinch bug, numerous plant-bugs, (fig. 13), 
squash bug, and certain beneficial species, such as soldier-bugs. 

Suborder Homoptera. — In this group the wings are of uni- 
form thickness and usually slope at the sides of the body, the 
beak arising from the hinder portion of the lower side of the 
head. In this suborder most injurious pests are found in the 
aphides (fig. 14), leaf-hoppers and the like. 



10 



INSECTS INJURIOUS TO VEGETABLES 



Suborder Physopoda. — The thrips have two pairs of wings 
of similar form — long, narrow, membranous, not folded, and 




Fig- 1 3.— Brown plant-bug (Euschfstus variolarius) . Adult at right; last 
riymph stage at left. Enlarged. (Howard, U. S. Dept. Agr.) 

with few or no veins. These are fringed with long hairs and 
do not fold, but are laid horizontally along the back when at 

rest 1 (fig. 15). 

Neuroptera. — This order 
has been subdivided by re- 
cent writers into numerous 
other orders, but as they are 
of comparatively little if any 
economic importance, these 





Fig. 15.— Enthrips tritici. a, Adult thrips; 
b, antenna; c, leg. All highly magnified. 
Fig. 14 -An aphis. Much enlarged (Aftgr Hubbard) u# S . Dept . Agr .) 

subdivisions need not be discussed here. The Neuroptera, in 
fact, have served as a "catch-all" for the groups that could not 

1 According to recent classification the Physopoda constitute a, distinct order, 
but the Parasitica, which includes the parasites of man and other mammals, 
is a suborder of equal rank with the Heteroptera and Homoptera. 



VALUE OF A KNOWLEDGE OF ENTOMOLOGY 



II 



be classified with other orders. Among neuropteroid insects of 
interest to the farmer are the aphis lions or young of the lace- 
winged flies (fig. 16) which are beneficial by feeding on noxious 
insects and the dragon flies, 
which also do some good in 
destroying injurious forms. 

The Coleoptera, Lepidop- 
tera, Hymenoptera, Neurop- 
tera and Diptera have what is termed a complete metamor- 
phosis, which means that they undergo four totally different 
stages, of egg, larva, pupa and adult or imago. In the remaining 




Fig. 1 6.— A lace-wing with eggs at right 




Fig. 1 7- —Tarnished plant-bug; four stages of nymphs. Enlarged 
(After Forbes) 

two orders, Orthoptera and Hemiptera, the metamorphosis is 
incomplete, which means that in the stages between the egg and 
the imago the insect undergoes only a gradual change, each 
successive substage (nymph) after the first being very like the 
one that precedes or follows it (fig. 17). 



NATURAL ELEMENTS IN THE CONTROL OF INSECTS 

The benefits which the agriculturist reaps from the friendly 
assistance of various forms of insects which prey upon nox- 
ious forms is very considerable. Every tiller of the soil 



12 



INSECTS INJURIOUS TO VEGETABLES 



should recognize their usefulness, but some are prone to ex- 
pect too much from them in the subjugation of farm pests, 
and opinions are so diverse that the grower is sometimes in 
doubt as to whether the insects which are indicated as his 
allies are not, in reality, pests. A little study is necessary in 
many cases to discriminate between noxious and innoxious 
species and those which are truly and exclusively beneficial. 

Organisms beneficial to agriculture may be variously classi- 
fied, but fall naturally into four groups. The most important 






Fig. 18. — Fiery ground-beetle, a, Larva; 
b, beetle. (From Riley) 



a 

Fig. 19. —A soldier-bug 
{Milyas cinctus). (Riley, 
U. S. Dept. Agr.) 



forms are: (i) predaceous insects, consisting of those which 
feed externally upon their prey; (2) predatory animals other 
than insects, such as birds and mammals; (3) parasitic insects 
which live in the bodies of their hosts; (4) fungi and diseases 
of bacterial origin. 

The weather has quite as great effect in the control of in- 
sects as in the yield of the crops themselves. Extremes of heat 
or cold, excess of moisture or dryness have the same effect 
on insect as on plant life. The results of severe rainstorms, 
sudden cold snaps and prolonged drought on many insect pests 
are well known. 

Of predaceous insects the most useful are undoubtedly the 



VALUE OF A KNOWLEDGE OF ENTOMOLOGY 1 3 

ladybirds 1 (fig. 9), from their destruction of aphides alone, 
although some forms also do as good if not even better work 
in limiting the numbers of scale insects. Ladybirds also devour 
the eggs and larvae of various other insects, and especially of 
soft-bodied forms. Several ground-beetles (fig. 18) live at the 
expense of cutworms and other vegetable-feeding caterpillars 
and the larvae of beetles. Of this number the great Lebia 2 
follows the Colorado beetle wherever it goes, and appears to 




Fig. 20.— Syrphus-fly (Syrphus ribesii). a. Fly; b, lateral view of head; 
c. larva or active immature form. All much enlarged. (Author's illustra- 
tion, U. S. Dept Agr.) 

have a very considerable effect in limiting its overproduction. 
Soldier-bugs 8 (fig. 19) of several species attack and kill soft 
larvae of beetles and of moths. Other important predatory 
enemies of noxious insects are syrphus and robber flies, spiders, 
and daddy long-legs or harvestmen. The syrphus flies 4 (fig. 20) 
are particularly useful in destroying aphides. Wasps of many 
forms provision their nests with the larvae of beetles and of 
moths, and certain species of mites help in reducing insects of 
pestiferous habits. 

1 Coccinellidse. 2 Lebia grandis. s Podisus spp. * Syrphidae. 



14 INSECTS INJURIOUS TO VEGETABLES 

Several kinds of birds, as also mammals, amphibians, and 
reptiles, are well-known enemies of noxious insects, and domes- 
tic fowls are of considerable value as destroyers of larvae, 
especially such as are not hairy, like the "slugs" of asparagus 
and potato beetles. 

Among beneficial birds, quail are important enemies of such 
pests as the potato beetle and boll weevil. Mammals include 
skunks, which kill great numbers of May beetles. Toads of 
the amphibians are particularly useful as insect destroyers. 

Chickens, ducks and turkeys 
are all used in a practical way 
by farmers for disposing of a 
variety of insects. Turkeys ap- 
pear to be naturally adapted as 
substitutes for "hand-picking" 
tomato or tobacco worms and are 
actually employed and loaned 
for such purposes, and swine 
Fig. 21 . — Pteromalus puparum, Male, are equally fitted for the destruc- 

Highly magnified. (Author's illustra- . r , . , , , 

tion, u. s. Dept. Agr.) tlon of white grubs and other 

subterranean pests. 

The parasitic enemies of noxious insects are legion, but 
their activity as useful allies to the farmer is to a large extent 
dependent on atmospheric conditions. As a general rule also they 
seldom appear in their greatest numbers until their injurious 
hosts have done more or less damage. Their principal useful- 
ness, then, is in so decimitating the numbers of noxious species 
in one season that few are left to prey upon crops the following 
year. 

The principal useful parasites belong to the family Hymenop- 
tera, four-winged creatures of wasp-like appearance and variable 
size. ■ Of these are the ichneumon flies, 1 chalcis flies, 2 bra- 
conids, 3 the egg parasites 4 and some others. 

1 Ichneumonidse. . ? Chalcidoidea. 3 Braconidee. * Proctotrypidse. 




VALUE OF A KNOWLEDGE OF ENTOMOLOGY 



15 



An excellent example of the value of parasites as insect 
destroyers is afforded by the imported cabbage worm. One of 
its parasites, Pteromalus puparum (fig. 21), destroys in some 
seasons from 80 to 90 per cent, of these "worms." Another 
parasite, Apanteles glomeratus was purposely introduced by the 
United States government about 1883. During the autumn of 
1904 this species held its host under complete control in the 
District of Columbia, killing every "worm" which came under 
the writer's observation. This species is shown in figure 2ix. 




Fig. 2lx— Apanteles glomeratus. a, Adult fly; b, cocoon ;.c, flies escaping from cocoons 
a, b, Highly magnified c, natural size. (Author's illustration, U. S. Dept. Agr.) 



CHAPTER II 

PREVENTION BY FARMING METHODS 

Having shown in a general manner what is desirable for the 
best understanding of the subject under consideration, it is next 
in order to point out how this knowledge may be utilized in the 
prevention or mitigation of injury. 

A knowledge of the origin and distribution of insects enables 
us to judge of the probable and ultimate spread of introductions 
from abroad and from one portion of our country to another. 
Thus we can predict, with a considerable degree of certainty, 
that certain species will not be injurious beyond certain bound- 
aries, and that others will widen their range beyond known 
limits. Knowing the effects of atmospheric conditions, of heat 
and cold, dryness and humidity upon insect reproduction, we can 
be forewarned of injury and can plan accordingly. Experience 
having taught that the clearing of uncultivated or neglected land 
is almost certain to be followed by depredations of insects which 
had inhabited the wild plants and weeds, we are enabled to 
plant such crops as will be least affected by these insects. 
Knowing what insects are controlled by predaceous, parasitic and 
other enemies, such as beneficial insects, contagious diseases, 
wild and domestic animals, we can in many cases, untilize these 
natural agencies in our warfare against them. 

Most of the different farming methods which A*ili be con- 
sidered are of use in combatting insect enemies of cereals; in 
short, without their employment it is impossible to avoid losses 
from these insects, as it is seldom practicable to use insecticides 
on growing grain. The usefulness of many of these methods 
is due to the slow spread of many species except at more or 

16 



PREVENTION BY FARMING METHODS 1J 

less regular periods of migration and the strong tendency which 
many have of depositing their eggs in the same field where they 
have bred or hibernated. 

The value of these methods in the treatment of the Hessian 
fly is summed up by Prof. F. M. Webster in the statement that 
"four-fifths of its injuries may be prevented by a better system 
of agriculture." 

SELECTION OF PLACE AND TIME FOR PLANTING 

With a knowledge of the insects which attain their highest 
development in sandy locations, in marsh land or in the neighbor- 
hood of woodland, we can prepare for attack from them after 
the ground has been cleared for planting. Much depends upon 
a judicious selection of the crop to replace weeds or to be grown 
in forest clearings or in land that has long laid waste. Unfortu- 
nately the crops frequently selected for planting in new land are 
the very ones most subject to attack, and if farmers generally are 
to preserve their crops from insect injury they must employ new 
tactics. Corn and other cereals, potatoes and strawberries are 
crops especially attractive to insects which have developed in 
unused land. They should therefore not be planted in new land 
until after some less susceptible plant be used as a first crop. 
Buckwheat and clover are less likely to be injured. 

Corn should not as a rule be planted in marshy tracts 
or in reclaimed river beds owing to the danger of injury 
from bill-bugs, root-worms, wireworms and the like. Nor 
should corn follow wild grasses, which are liable to be affected 
by the same classes of insects as well as cutworms and white 
grubs. 

Next in order is the choice of the proper time to plant to 
avoid insects which are liable to' attack the crops which we in- 
tend to grow. With early and late planting must be combined 
occasional planting between two generations of an insect, and 
the timely disposal of the crop, particularly if this is damageable. 



l8 INSECTS INJURIOUS TO VEGETABLES 

Late planting is practiced against numerous insects with ex- 
cellent success, the object being to have the crop appear after 
the disappearance or dispersion of the insect whose ravages are 
feared. It is, in fact, a standard remedy against some insects. 

THE MAINTENANCE OF VIGOROUS GROWTH 

If plants be weakened through atmospheric or other cause or 
through a combination of unfavorable conditions they are as a 
general rule more subject to injury by insects, but there are 
many crop plants, as for example certain varieties of wheat, that 
the ranker the growth the more they are subject to infestation 
by such insects as the Hessian fly. 

Some have claimed that weak plants only are subject to injury, 
and that plants might be grown by artificial methods for the 
production of such great vigor that insects would not seriously 
damage them. Although this might be possible with a limited 
number of plants, we can not now procure all of the most favor- 
able conditions. As an instance, we have only to cite the re- 
ported successful use of kainit and nitrate of soda as a remedy 
for wireworms and some other insects in New Jersey, and their 
failure when applied in other states. Possibly soil and atmos- 
pheric conditions have in some instances had some bearing upon 
these failures. Most failures, however, are due to wrong methods. 

BURNING OVER FIELDS AND WASTE LANDS 
A farm practice in favor in many regions against cereal-feed- 
ing insects consists in burning over fields after harvest or be- 
fore plowing. It affects particularly such insects as hibernate 
on or just below the ground. Among well-known pests that 
can be reached by this method are cutworms, many of which live 
all winter long above the earth's surface partially grown, also 
webworms, grasshoppers, aphides and plant-bugs, and some 
forms of beetles and other insects which hibernate in the adult 
stage at or near the surface. 



PREVENTION BY FARMING METHODS I9 

CROP ROTATION 

One of the best of farming methods is crop rotation, as it 
serves several purposes. If pursued on scientific principles it is 
not only a benefit to the land, but is one of the easiest means of 
preventing attack from insects, fungous and other diseases, and 
weeds. In a general way it may be said that crops of like kind, 
that is, belonging to the same botanical groups, and much sub- 
ject to insect attack, should not be planted in successive years 
in the same fields. Thus it is inadvisable, to plant corn in old 
wheat fields, and it is equally unwise to grow small grains after 
corn. Where insects occur like the bollworm, which attacks 
several plants, injuring tomato fruit, corn ears, bean pods, etc., 
in similar manner, still greater care is necessary in selecting 
the land for planting. It follows that it is bad practice to plant 
corn after tomatoes or tomatoes after corn, or to plant either 
of these crops in or near cotton fields. 

Here is where a knowledge of botany sufficient to enable the 
grower to know the botanical families to which his crops, as 
well as the weeds, belong becomes of value; since with the ex- 
ception of insects known as general feeders, most species feed 
by preference on one or more plants of the same botanical group. 
Thus an insect destructive to cabbage will attack any cole crop, 
such as turnip or radish, and weeds such as wild mustard and 
pepper-grass ; hence care should be used not to plant cabbage in 
fields in which the other plants have grown. The same rule holds 
with plants of the cucumber kind. Melons should not follow 
squashes, nor pumpkins cucumbers. Rotation of crops is prac- 
tically the only means of dealing with some of the most im- 
portant insects, among which are the western corn root-worm. 
Where diversified farming is practiced, such leguminous plants 
as crimson clover and cowpea are most useful as alternates, be- 
cause valuable as soil restorers, and not as a rule subject to 
serious insect injury. 



20 INSECTS INJURIOUS TO VEGETABLES 

DIVERSIFIED AGRICULTURE 

Entire plantings are frequently failures because growers rely 
on single, or, at best, two or three crops for a livelihood. The 
practice of growing large areas to cotton in the South is an ex- 
ample. Occasionally this is varied by corn or tobacco, and all 
three crops are likely to be injured by the same insects, e. g., by 
the bollworm, corn-ear worm or tobacco budworm, as this one 
species is variously termed. In Texas there was at one time 
the threatened danger of an abandonment of cotton culture 
owing to the rapacity of the boll weevil. The large appropria- 
tions that have been made available by Congress for the con- 
trol of this pest should result in materially reducing the losses 
occasioned by it, which now bids fair to seriously hamper the 
production of this staple which nets our country $500,000,000 
or more annually. The melon or cotton aphis has done great 
damage in Texas since the beginning of the new century and 
various crops in the South are threatened with new pests. It 
is quite a problem, therefore, to decide what may be grown 
most advantageously. 

Other striking illustrations of the danger of cultivating a 
single crop can be pointed out. In some years in the past it was 
simply impossible for truckers in parts of Maryland and Virginia 
to make a living from cabbage, or other cruciferous crops or 
from melons and other cucurbits, but by growing several crops 
of widely different kinds they make a profit. 

In the Northeast the farmer does not have such problems with 
which to contend and yet raises many crops, keeping his hands 
busy nearly the year round, and there is no excuse for growers 
in the South and elsewhere cultivating only a few crops when 
by diversified or general farming losses from insects, from plant 
diseases, and from adverse climatic conditions could be avoided/ 



PREVENTION BY FARMING METHODS 21 

FALL PLOWING AND CULTIVATING 

One of the best methods of deterring insects from injurious 
attack, comparable with clean culture, burning over, submersion 
and the like, is fall plowing and other ways of cultivating. The 
process may be varied by harrowing, disking, and raking, and 
sometimes in cases of serious infestation a cross-plowing is 
advisable. The object of fall plowing is to bring the insects 
that are feared to the surface where they will be exposed to cold 
and other elements and to natural enemies such as domestic and 
wild birds and mammals. This method is particularly valuable 
to prevent the recurrence of severe attacks and is beneficial for 
most forms of insects which hibernate under or near the surface 
of open fields, meadows and like places. It is particularly indi- 
cated for many insects affecting cereals, cucurbits and some 
other vegetables, and where corn and other crops subject to 
injury by white grubs, root-worms and wireworms and other 
subterranean insects, as well as cutworms, grasshoppers and 
others, are to be planted in sod or weedy land. Where the forms 
of insects mentioned are extremely troublesome, the land should 
be very thoroughly broken, and the insects, whether larvae, pupae, 
or adults, should be as much exposed as possible. This remedy 
is very effective in cold climates since the exposed insects are 
unable to obtain secure shelter before severe frosts. 

Fall plowing should be practiced for most crops where it does 
not interfere with other methods of cultivation. 

The numbers of the squash-vine borer can be greatly reduced 
by lightly harrowing the surface of infested fields after harvest 
so as to bring the cocoons to the surface, and then plowing in 
the spring to a uniform depth of six inches or more, so that the 
adults will not be able to issue. 

Disking, or cultivation with a disk harrow, is particularly 
recommended against the fall army worm, which hibernates 
as pupa near the soil surface. A somewhat similar method of 



22 INSECTS INJURIOUS TO VEGETABLES 

treating lawns infested by army worms, and root webworms, 
consists in going over them thoroughly with a long-toothed 
steel rake. 

CLEAN FARMING METHODS 

The most valuable of all methods of controlling destructive 
insects, if we except the employment of insecticides, consists in 
the observance of clean cultural practice, and when with this 
we combine the judicious use of other methods, including me- 
chanical ones, only moderate use of poisons, employed at the 
proper time, is necessary. It is a more or less complete safe- 
guard against the bulk of insects that ravage our crops. 

Clean farming should always be practiced in the growing of 
crops that are liable to severe insect injury. Where the char- 
acter of a crop will permit, still more can be accomplished by 
using portions of the same or a similar crop as baits. In ad- 
dition, it is also desirable to employ as trap crops such weeds as 
the insects normally affect and which already grow in the fields, 
while in many cases it has been found of value to plant weeds 
or other crop plants to lure the insects from the main crop. 
Clean methods of management, though indicated as protective 
against most insects, is a practical necessity where there are 
many species that injure fall crops, such as cabbage, turnip and 
other crucifers, and for such insects as pass the winter in rub- 
bish in the fields that they have ravaged. 

FARM INSPECTION 

An old proverb, "An ounce of prevention is worth a pound of 
cure," is as applicable to man in relation to insects which injure 
his crops as to other matters which affect his well-being. Eter- 
nal vigilance is also the price of a good crop. The fact that 
the greatesL injury due to such insects as army worms, cut- 
worms, blister beetles and the like is accomplished before their 
presence is known, indicates the value of prompt action in the 
treatment of the crops affected. Too frequently attack is un- 



PREVENTION BY FARMING METHODS 2$ 

noticed until damage is beyond repair, and this might be averted 
if the grower would only employ some simple farm practice like 
fall plowing. 

Promptness cannot be too strongly urged, for the application 
of remedies if too long deferred may be useless. As soon as a 
crop is planted it should be inspected every few days for signs 
of injury. If plants growing under the same conditions make 
unequal growth, over a considerable area, the backward plants 
should be examined for evidence of insect work. Insect injury 
is manifested in different ways, as has already been described 
in the Introductory Chapter (page x). 

After crops have made some growth, a weekly inspection will 
in ordinary cases suffice until the danger point has passed; and 
as attack usually begins on the borders of a field, by walking 
around it most forms of insect injury may be detected. Pre- 
ventive work, such as clean culture, rotation and fall plowing, 
should be instituted as a part of the routine of farming; and if 
systematically pursued losses through insect ravages will be 
reduced to a minimum; while prompt action at the very outset 
of attack, in the application of insecticides or mechanical 
methods will, in exceptional cases, save the crop. 

COOPERATION IN THE CONTROL OF INSECTS 

The grower who institutes practical methods for the control 
of insects which menace his crops has a distinct advantage over 
one who does not. The enterprising farmer is enabled to ob- 
tain a good yield while the careless grower stands a chance of 
a money loss on his crop. It has long been recognized that 
insects of many forms are a direct benefit to the progressive 
man, who farms on scientific principles, enabling him to pre- 
serve his crops while the damage that may be done to his more 
careless neighbors enhances the market value of what the 
scientific farmer raises. This is a decidedly narrow-minded and 
selfish way of looking at the subject. 



24 INSECTS INJURIOUS TO VEGETABLES 

Large corporations like seedsmen, canners, and picklers, plant 
very extensive areas and employ others in growing the same 
crops. Such firms provide seed and machinery, and keep posted 
on what will benefit not only their own interests, but those who 
labor for them. This applies to the means of controlling in- 
sects, including the purchase of insecticides and spraying ap- 
paratus, and by purchasing at wholesale they greatly reduce the 
cost for themselves and their co-laborers. The scope of this 
work might be extended (and perhaps is in use in some measure) 
to those who grow on a smaller scale, the farmers of a given 
locality having a community of interests pooling their interests 
for the purpose. Growers having small areas are often so 
little troubled with insects that it does not pay to buy expensive 
outfits; and insecticides cost at retail frequently two or three 
times as much as when purchased in quantity. For example, 
bisulphid of carbon, a standard remedy for the melon aphis, 
bean and pea weevils and root-maggots, costs only 10 cents a 
pound in fifty-pound lots, and from 20 to 30 cents when bought 
in smaller quantity. This difference could be saved by the co- 
operation of several neighbors, and it could be extended to the 
purchase of expensive spraying outfits. 

Co-operation is of especial value in the control of insects such 
as the squash bug, cucumber beetle, harlequin cabbage bug, and 
cabbage looper, that cannot be held in subjection by ordinary 
poisons. If growers who suffer most could induce neighboring 
farmers to employ clean farming methods and crop rotation, the 
ravages of these pests would be greatly reduced. The harlequin 
cabbage bug is quite resistant to poisons, and since about the 
year 1900 it has been so nearly exterminated in its northern 
range, that if farmers would work together when it again makes 
its appearance northward and use trap crops over large areas, 
for example over townships, the insect might be prevented 
for several more years from regaining its lost foothold. This, 
with clean methods of cultivation, would leave little else neces- 



PREVENTION BY FARMING METHODS 25 

sary to keep the insect down, unless by carelessness it were 
permitted to return unmolested to its old haunts. Immeasurable 
benefits would undoubtedly accrue by the subordination of self- 
interest for the common weal. Indeed this subordination is only 
apparent and it has been pointed out that one of the best, as it 
is the noblest, methods of self-help consists in helping our 
fellow men. 




Fig. 2\y. — A simple coal-tar pan to be drawn by hand (After Riley) 



CHAPTER III 

MECHANICAL METHODS OF DESTROYING 
INSECTS OR PREVENTING INJURY 

Many valuable mechanical methods of controlling insects are 
employed, such as hand-picking, ''bugging" or beating, collecting 
in nets or in hopper-dozers, ditching, disking, driving and others. 

Hand-picking is useful for large conspicuous inactive insects, 
such as the squash bug, potato beetle, cutworms and similar 
caterpillars. It is one of the simplest measures that can be em- 
ployed, and is valuable where other means cannot be used and 
where labor is cheap. 

Bugging. — This term is often used for jarring and beating in- 
sects from low plants into pans containing water and a thin 
scum of kerosene. The water prevents the insect from es- 
caping, and the floating kerosene kills every insect which comes 
in contact with it. 

Collecting in nets. — Hand nets of muslin or cheese-cloth such 
as school children employ for the capture of butterflies, are use- 
ful against some insects which affect truck crops. Among such 
are the tarnished plant-bug, which affects about equally vege- 
tables and small fruits. By sweeping over the plants to be 
protected and the weeds and grasses of the vicinity, thousands 
can be captured in a short time, and they can then be killed by 
throwing them into a fire or into hot water. 

Collecting in hopper-dozers. — Many forms of these death-deal- 
ing devices are in use for grasshoppers (see figs. 213; and 2iz) 
and for leaf-hoppers, which will be described in the discussion 
of those insects. 
26 



MECHANICAL METHODS OF DESTROYING INSECTS 



2? 



Brushing methods. — Different methods of brushing more or 
less sluggish insects from their cultivated food plants have been 
in vogue for many years. Potato beetles and their larvae may 
be brushed from potato plants by means of a short-handled 
broom, a second person to follow dragging by horse power a 
bundle of brush or a harrow to crush the insects and bury them. 
This process is simplified in the treatment of the asparagus 




Fig. 21<?.— A canvas hopper-dozer to be drawn by horse, (After Riley) 

beetles. It consists in beating or brushing the insects from the 
plants with a stick so that they will drop to the bare ground 
on a hot dry day. The larvae are delicate creatures, crawl very 
slowly, and few are able to regain the shelter of the plants and 
die from exposure to the heated earth. A somewhat more com- 
plicated system came into rather extensive use in 1900 against 
the pea aphis. It is known as the brush and cultivator method, 
and at the time of writing is the best remedy that has been de- 
vised for this pernicious species. It will be described in dis- 
cussing pea aphis remedies. 

Cloth covering. — To prevent injury from some forms of in- 
sects to young plants before they are fairly above ground early 
in the season cloth coverings are used. A cheap frame may be 



28 INSECTS INJURIOUS TO VEGETABLES 

made by cutting a barrel hoop in two so as to form two semi- 
circles, which are then placed at right angles to each other, and 
the lower ends inserted into the ground with the curve upper- 
most. This is then covered with gauze or similar material, held 
in place with earth packed about the edges, to prevent the 
beetles working under it. It is necessary to keep the plants 
covered only while they are young, and the same covering may 
be used year after yean Such covers are much used against 
the striped cucumber beetle, and radishes have been successfully 
protected from root-maggots. 

Trapping. — Several methods of trapping insects are practiced 
with success. Trapping under boards, shingles, chips, etc., is 
useful for squash-bugs and cutworms and if employed properly 
will serve as a means of destroying many pests. In the case 
of cutworms poisoned baits are placed under such traps. 

Pruning and the destruction of affected parts, practiced with 
benefit against many tree-borers, are useful methods for killing 
some vegetable feeders, e. g., aphides or "lice" when congre- 
gated on seedstalks of crucifers, etc. 

Miscellaneous mechanical remedies. — Such remedies as ditch- 
ing, disking and driving are applicable to only a few forms of 
insects and will be mentioned in the body of the present work as 
remedies for those insects where described. Ditching is prac- 
ticed against the army worm, as is also disking, and such insects 
as blister beetles and cucumber beetles may be driven by various 
means from cultivated fields. 

Repellents. — Various substances have been advised in the past 
and are claimed by "knowing ones" to be valuable as preventives 
Of insect attack, but comparatively few deterrents will stand a 
thorough test The best for use on vegetable crops will pres- 
ently receive mention because of their value as insecticides or 
fungicides. These are: Tobacco; carbolic acid, used in emul- 
sified form; Bordeaux mixture; kerosene emulsion; sulphur, 
when freshly applied ; and fish-oil soaps. Certain substances like 



MECHANICAL METHODS OF DESTROYING INSECTS 29 

ashes and road dust, finely pulverized and sifted on young leaves 
serve to drive insects to other clean leaves which should be 
poisoned. Substances which are of little or no practical use as 
repellents, for vegetable insects at least, are legion. Among 
those for use as topdressings, or about the soil of the plants, 
which do not commend themselves or which produce indifferent 
results are : Bone dust, soot, coal dust, liver of sulphur, lye, ben- 
zine, naphtha, naphthaline, alum water, salt, saltpetre, etc. 

Bordeaux mixture is one of the most valuable insect deter- 
rents and is particularly useful for flea-beetles, leaf-beetles and 
other foliage-feeders. Its value as a fungicide is too well known 
for further comment. The formula follows: 

Into a 50-gallon barrel pour 30 gallons of water, and sus- 
pend in it 6 pounds of bluestone in coarse sacking. Slake 4 
pounds of fresh lime in another vessel, adding water slowly 
to obtain a creamy liquid, free from grit. When the bluestone 
is dissolved add the lime milk slowly with water enough to 
fill the barrel, stirring constantly. 

With insufficient lime the mixture sometimes injures the 
foliage, and it should be tested with a solution obtained by dis- 
solving an ounce of yellow prussiate of potash (potassium fer- 
rocyanide) in one-half pint of water. If there be insufficient 
lime in the Bordeaux mixture the addition of a drop or two 
of this solution will cause a brownish-red color, and more lime 
should be added until no change takes place when the solution 
is dropped in. Use the Bordeaux mixture promptly, as it de- 
teriorates on standing. 

Stock solutions of both the bluestone and lime may be kept 
for any length of time. Make the stock bluestone by dissolving 
in water at the rate of 2 pounds to the gallon. The stock lime 
is slaked and kept as a thick paste. Cover both mixtures, to 
prevent evaporation and keep the lime moist. For the 50-gallon 
formula add 3 gallons of the bluestone solution to 50 gallons 
of water, and introduce the stock lime slowly until there is no 
reaction with the testing solution. — Galloway. 



CHAPTER IV 



INSECTICIDES AND THEIR USES 

The most approved means of controlling insects consists in 
the use of poisonous mixtures administered in the form of a 
spray, wash, or dry powder in conjunction with such methods of 
farming, as fall plowing and rotation of crops, which tend to 
decrease the chances of injury from insect attack. 

Insecticides, or the substances used for the destruction of in- 
sects, may be classified as internal or stomach poisons, and ex- 
ternal or contact poisons. The former kill by being eaten with 
the insects' food, the latter by direct contact causing corrosion 
of the bodies of the insects, or the closing of their breathing 
pores. 

STOMACH POISONS, ARSENICALS, ETC. 

Paris green. — Of the various internal poisons in use against 
insects none are so valuable or so much used as Paris green, 1 
the standard remedy against biting or chewing species, which 
include the bulk of injurious forms, such as cutworms and other 
caterpillars, beetles, grubs, slugs, etc. Paris green is applied in 
two ways, — dry and as a spray, the latter being the method 
most extensively used, as it is cheaper and more effective, 
answering all the purposes to which dry powders are put. A 
spray is prepared by combining one pound each of the poison 
and fresh slaked or quick lime with from 75 to 150 gallons 
of water. A slight excess of lime is advisable. A somewhat 

1 Paris green is now chemically known as copper aceto-arsenite ; in other 
words, it is a chemical compound of oxid of copper, acetic acid and arsenious 
acid, and when properly combined the proportions of the different chemicals 
are as follows: copper oxid, 31.29 per cent.; acetic acid, 10.06 per cent.; 
arsenious acid, 58.65 per cent. 

30 



INSECTICIDES AND THEIR USES 31 

stronger mixture can be used on resistant plants like potato, and 
a weaker solution (1 to -200) must be made for young and 
delicate foliage. 

For the proper preparation and application of this and other 
sprays a sprayer or spray pump is necessary. The Paris green 
should first be mixed with a small quantity of water into a thin 
paste before the bulk of the water is added, and should then be 
thoroughly mixed by churning in the force-pump. As the mix- 
ture is only a mechanical one the Paris green tends to sink to 
the bottom, and to avoid this it must be constantly stirred while 
being applied, otherwise the mixture near the bottom of the 
tank or reservoir will become so strong as to scorch the foliage. 
Care should be exercised in the purchase of a spray pump that 
it be equipped with a proper agitator. 

When applied dry, it is generally mixed with from 10 to 20 
parts of flour, plaster, or lime. This remedy affords best results 
early in the season on young plants. It should be dusted on 
preferably when the dew is on, or after a shower, and by means 
of powder guns or bellows, or the so-called "dust-spray" ma- 
chines, so as to cover the plants and leave as little surface as 
possible for food for the first-appearing insects. 

It is often advisable to use Bordeaux mixture in combination 
with an arsenical, especially if a disease is present. This is 
a valuable insect repellent as well as a standard fungicide, and 
it operates also against different forms of blight and other 
diseases which may threaten the crop. It is used as a diluent 
instead of water . and in the same proportions, and prevents 
scorching. Its preparation is discussed on page 28. 

Paris green is more usually recommended for general pur- 
poses because it is known to most farmers, can be obtained in 
drug stores anywhere, and because of its supposed cheapness. 
Its use, however, is being superseded in some degree by arsenate 
of lead and other arsenicals. 

Paris green is very frequently adulterated by unscrupulous 



32 INSECTS INJURIOUS TO VEGETABLES 

dealers, e. g., with white arsenic, which makes the liquid mixture 
(containing an excess of free arsenic) still more scorching in 
its effects on vegetation. The New York (Geneva) Experiment 
Station has ascertained that this insecticide possesses about one- 
third the fungicide value of Bordeaux mixture. 

Arsenate of lead, lead arsenate or "disparene" has the ad- 
vantage of being less harmful to growing plants and adheres 
better to the leaves than other arsenicals. It is less apt to burn 
delicate foliage, hence does not require the same care in its 
application as is necessary for Paris green, and can, moreover, 
be obtained ready made on the market. Numerous brands are 
for sale, and care should be exercised to obtain a good quality 
as some alleged arsenate of lead preparations contain free 
arsenic. The commercial preparations are mostly like paste or 
putty and must be worked in a little water in a bucket before 
being added to the spray tank. 

It is prepared by combining acetate of lead (6 or 7 parts) 
with arsenate of soda (3 parts). In spraying it can be employed 
at any strength from 3 to as high as 12 pounds to 100 gallons 
of water without injury to most vegetable crops. Its cost at 
present writing is 12 to 15 cents a pound when purchased in 
bulk. Quite a number of other arsenicals have been more or 
less used as insecticides and some of these are of considerable 
value while others have no especial advantages over Paris green 
or arsenate of lead, or are decidedly inferior. 

London purple was formerly used in spraying. As sold in 
the market its composition is unstable owing to its being apt 
to be adulterated, and it is very caustic, hence liable to scorch 
tender foliage. For these reasons it is rapidly going out of 
use. As a spray it is applied in the same proportions as Paris 
green, as is also arsenite of copper. 

Arsenite of copper (Scheele's green or "green arsenoid") is 
of similar composition to Paris green, and is even superior 
owing to its more rapid effects and less liability to produce 
scorching. It is, however, not as yet so readily obtainable, 



INSECTICIDES AND THEIR USES 33 

White arsenic (pure arsenious acid) is the active principle 
of all the arsenicals. It is particularly dangerous when used 
alone in solution, but as it is the cheapest of the arsenicals it is 
employed in the preparation of poisoned baits for cutworms and 
grasshoppers. Combined with lime it forms arsenite of lime. 

Arsenite of lime has been highly recommended by those who 
have tried it. It is prepared by such methods as follow: 

The Kedzie formula: Boil 2 pounds of white arsenic and 8 
pounds of sal-soda 15 minutes in 2 gallons of water. Put into 
a jug, label "poison" and lock it up. When ready to spray, 
slake 2 pounds lime and stir into it 40 gallons water, adding 
a pint to a quart of the mixture from the jug. 

Formula No. 2 : Boil together 1 pound white arsenic, 2 pounds 
lump or stone lime and 3 gallons water. Dilute with about 
200 gallons of water before spraying. 

Still other arsenicals possess insecticidal properties. Of these 
"pink arsenoid" has given good results experimentally. "White 
arsenoid" has been practically withdrawn from the market. 
"Paragrene" is reported as having equal insecticide value with 
Paris green, is about as likely to burn foliage, but remains 
longer in suspension. 1 

The arsenicals are also useful in the preparation of poisoned 
baits, which will be discussed in the consideration of cutworms 
and locusts or grasshoppers. 

Harmlessness of arsenicals when properly applied. — Chemical 
analysis has shown that cabbage which has been dusted or 
sprayed with an arsenical in the way prescribed, and then 
prepared for cooking in the usual manner a week later has not 
even a trace of arsenic remaining. The use of arsenicals against 
cabbage worms is almost universal, although growers are some- 
times loath to acknowledge the fact for fear of the loss of 
customers who are not fully acquainted with the harmlessness 

More detailed directions for the preparation of the arsenicals here dis- 
cussed are given in Farmers' Bulletin 127, U. S. Department of Agriculture. 



34 INSECTS INJURIOUS TO VEGETABLES 

of this remedy. There are no authentic recorded instances 
known to the writer of poisoning from the consumption of 
cabbage or other vegetables treated with an arsenical. Ac- 
cording to Gillette, 28 cabbages dusted in the ordinary way 
would have to be eaten by a human being at one meal in order 
to produce poisonous effects ! It is preferable, however, in 
order to avoid all danger, to use other insecticides in the case 
of vegetables soon to be eaten. 

Caution. — It is advisable in using all arsenicals to see that 
they are correctly labeled and kept under lock and key, as they 
are dangerous to human as well as other animal life. 

The utensils employed in preparing arsenical mixtures should 
be thoroughly cleansed after use. 

Lime (oxid of calcium) possesses considerable value as an 
insecticide and repellent, its efficiency being in proportion to its 
dryness and caustic quality. It is more effective against delicate 
and moist insects, such as the larvae of asparagus and potato 
beetles and root-maggots. For leaf-feeding species it is sifted 
on the plants and kills by contact, literally burning holes into 
the soft bodies of the larvae which it touches. Certain root- 
maggots and white grubs are without doubt largely attracted 
to gardens by the presence of manures and decomposing veg- 
etable matter, and if this be powdered with lime, finely sifted, 
it soaks into the material with rains and, moreover, acts as a 
deterrent, especially against the flies which produce the root- 
maggots. It is useful also for slugs or snails. 

Fresh air-slaked or quick lime should be used, as when stale 
it loses its caustic properties. 

Gas lime is of value in clearing infested land of white grubs 
before planting some crops. It is a refuse product of gas plants 
and may be obtained frequently merely for the cost of hauling. 
It contains much gas in a crude form, and to be of greatest 
value should be fresh so as to give out a strong gassy odor for 
several days after application. When applied to lawns it is 



INSECTICIDES AND THEIR USES 35 

sprinkled over the surface as a top dressing. In fields of potato 
it should be applied between rows and covered by earth, by 
drilling or other process, as there is a possibility of injury to 
plants, and this method should be used experimentally at first. 
The amount to use will vary according to the degree of infesta- 
tion by white grubs and other conditions. It has been employed 
at about the rate of 4 barrels to 100 square feet of ground on 
a lawn with the result that the spring after application all 
forms of vegetation, including weeds, came up, and only five 
or six white grubs could be found. In Europe gas lime has 
been used with some success in connection with other remedies 
for wireworms at the rate of i l / 2 tons to the acre. 

The best time to apply the lime is in September, after the 
crop is made. 

Caution. — There is always danger to plant life in the use 
of gas lime,- hence before employing it on growing crops on a 
large scale it should first be used experimentally. 

Hellebore, or white hellebore (Veratrum album) is less dan- 
gerous than the arsenicals, hence .has some votaries for its use 
on cabbage and other plants soon to be eaten. Its use is open 
to the same objection as pyrethrum that it loses its insecticidal 
properties by exposure to the air. It is also poisonous to 
man and domestic animals. It is a specific against the slugs or 
, false-worms (none of which commonly affect vegetables), which 
attack raspberry, currants and other bush fruits. As many truck- 
growers raise bush fruits it might be added that it is used in 
both dry and liquid form, but can be applied more thoroughly 
as a spray, J / 2 ounce of powder to 2 gallons of water. Dr. 
James Fletcher recommends its employment as a remedy for 
certain kinds of cabbage pests, including "worms" and root- 
maggots. On the latter it is applied at the rate of 2 ounces of 
powder to the gallon of water, and applied with a force-pump 
about the infested roots. 



36 INSECTS INJURIOUS TO VEGETABLES 

CONTACT POISONS 

Kerosene emulsion is the standard remedy for sucking 
insects such as aphides or plant-lice, plant-bugs and the like, 
and is of value against other soft-bodied insects, which cannot 
for different reasons be safely poisoned by Paris green and 
similar insecticides. The best form for ordinary use is the 
kerosene-soap emulsion, made by combining 2 gallons of kero- 
sene, J / 2 pound of whale-oil soap, or 1 quart of soft soap with 
1 gallon of water. 

The soap should be dissolved in boiling water and then poured 
while boiling (away from the fire) into the kerosene. The 
mixture is then churned violently for about five minutes by 
means of a force-pump and direct-discharge nozzle throwing 
a strong stream by pumping the liquid back upon itself. At the 
end of this time the mixture will have become of the con- 
sistency of thick cream. Properly prepared an emulsion will 
keep almost indefinitely, and should be diluted only as needed 
for use. For most insects, except scales, the staple emulsion 
should be diluted with from 15 to 20 parts of water. A 10 per 
cent, solution, or even stronger, is sometimes necessary. 

In the preparation of kerosene emulsion a force-pump is a 
necessity, since, if not made according to directions, a perfect 
emulsion is not formed. There is then danger of injury to the 
plants by the kerosene, as also useless waste. There is also 
danger and waste if the insecticide is not applied by means of 
a fine nozzle in the form of a spray, which should be fine and 
mist-like. It should be sprayed only long enough to cover the 
plants and not so that the liquid forms into globules and 
runs off. 

In the practical application of this insecticide certain setbacks 
are frequently encountered. One of these is due to the fact 
that aphides and many other sucking insects feed more or less 
exclusively on the under surface of leaves, which necessitates 



INSECTICIDES AND THEIR USES $7 

an under-spraying of the leaves in order to reach the pests. This 
is frequently of difficult accomplishment owing to the thick 
growth of the plants after they have got well started, and the 
fact that many leaves overlap others. An example of the dif- 
ficulty experienced in spraying for aphides is afforded in the 
pea aphis, particularly where peas are grown broadcast, which 
does not permit the driving of a machine through the fields. 
The leaves interlace and intertwine in such a manner that the 
insects cannot be reached. The same is the case with melons 
after they have attained any growth. There is also danger of 
injury to the vines by the wagon wheels and the horse in going 
through the fields. 

For success with this remedy it is in many cases absolutely 
necessary that the emulsion should be applied so that it will 
actually come in contact with or strike the insects against which 
it is directed. 

Kerosene-milk emulsion is sometimes used, but it is hardly 
as satisfactory as kerosene-soap emulsion, since the soap in the 
latter has also considerable killing and repelling power. 

Carbolic-acid emulsion. — For some purposes it is desirable to 
add to kerosene emulsion a quantity of carbolic acid, e. g., for 
the treatment of various root-infesting insects, such as root- 
maggots affecting seed-corn, onion, and cabbage. This emulsion 
is prepared at the rate of I pound of soap, I gallon of water, 
and y 2 gallon of crude carbolic acid, and is diluted with from 
35 to 50 parts of water. It has been found quite effective 
against root-maggots, the plants showing no injury due to the 
insecticide. It should be applied a day or two after the plants 
are up, or, in case of crops that are transplanted, the da^ after 
they are set in the field, and should be repeated every iweek or 
ten days until about the latter half of May. Carbolic acid is 
at once a repellent and a contact and stomach poison. It should 
be handled with care as it is corrosive ! 

Corrosive sublimate (Bichlorid of mercury) is prepared by 



38 INSECTS INJURIOUS TO VEGETABLES 

mixing 2 to 2^ ounces of the poison with 15 gallons of water. 
The poison is first dissolved in 2 gallons of water, and more 
is added to make 15 gallons. This is allowed to stand 5 or 6 
hours, and the solution agitated several times. This is a fun- 
gicide as well as insecticide, and is useful both for potato scab 
and the potato scab gnat. Seed potatoes are soaked from an 
hour and a half to three hours in this solution before planting. 
As corrosive sublimate is a violent poison, unusual care should 
be exercised in handling it. It should not be mixed in metallic 
vessels, nor exposed where it might be eaten by stock. 

Formalin is prepared by mixing 8 ounces of 40 per cent, 
solution with 15 gallons of water, and is used for the same 
purposes as corrosive sublimate, but is less poisonous. Seed 
potatoes are immersed two hours. 

Soap preparations. — Soap solutions are valuable as washes in 
the control of noxious insects. Both hard and soft soaps are 
used, but "whale-oil" soaps, usually manufactured of fish-oil, 
are of greatest value. A solution of fish-oil soap is prepared 
by dissolving 1 pound of the soap in from 4 to 10 gallons of 
water. On some hardy plants a strength of 1 pound of soap 
to 2 gallons of water can be used, but this is harmful to delicate 
plants and must be employed with caution. A wash of 1 pound 
soap to 6 or 8 gallons is of most value for aphides, minute leaf- 
bugs, leafhoppers, and thrips, and some forms of small larvae. 
These coaps possess no particular advantage, however, over 
kerosene-soap emulsion and are, in fact, less effective against 
vegetable-feeders. Castile or "neutral" soaps, among which are 
ivory soap, are much used on plants grown under glass and as 
a means of arresting the ravages of "red spider" and the same 
insects that have been mentioned. 

Cold and hot water are properly speaking contact insecticides 
of value in the destruction of minute insects such as aphides. 
A strong spray of ice cold water applied to louse-infested plants 
is a very useful remedy, but hot water is still more effectual 



INSECTICIDES AND THEIR USES 39 

as a means of riddance of these pests, The latter is most ap- 
plicable to such plants as cabbage, which withstands a high 
degree of temperature, which would be hurtful to less hardy 
plants. A water thermometer is employed, and care is observed 
that the temperature does not reach far above 150 , the 
scalding point for most plants. From 125 to 135 is sufficient 
for the destruction of most insects, but applied still hotter where 
possible is still more effective. Cabbage will withstand a tem- 
perature of 180 without special harm. When setting out cab- 
bage and some other plants they can be freed from "lice" by 
dipping them into water heated to between 125 and 150 . Hot 
water cannot be thrown in a spray owing to its cooling too 
rapidly, and it is necessary if it is to be thoroughly effectual 
for it to actually strike the insects which it is desired to destroy. 
Where only a few plants are to be protected and it is possible 
to reach the "lice" with water applied with a garden hose, 
syringe or spraying machine their work can be checked. Such 
as come in direct contact with a stiff spray at an ordinary 
temperature are unable to survive, while many that are dis- 
lodged cannot return to the plants as most of them are wingless 
and unable to crawl any distance, particularly if the ground be 
dry and hot. 

INSECTICIDES WHICH KILL BY SUFFOCATION 

Under this caption will be included insecticides which do not 
properly fall under the heading of either stomach or contact 
poisons. Of these are pyrethrum; tobacco, which acts both as 
a repellent and, when vaporized, as a destroyer of aphides and 
thrips ; bisulphid of carbon and hydrocyanic-acid gas, two deadly 
gases, and some others. 

Pyrethrum. — Several forms of insect powder, the pulverized 
dry flowers of different forms of daisies, are on the market 
under such names as Persian and Dalmatian insect powder. 
One of these is buhach, made exclusively from Pyrethrum 



40 INSECTS INJURIOUS TO VEGETABLES 

cineraria folium. It was carefully tested years ago by the De- 
partment of Agriculture at Washington, and although not use- 
ful against all forms of insects, is very valuable for household 
pests, aphides, and small plant-bugs and caterpillars. It is best 
used dry by dusting the plants affected with an insufflator or 
bellows while wet with dew. It acts by closing the breathing 
pores of the insects, and has the advantage of being harmless 
to man and the higher animals. It is also used in liquid form, 
as a spray, the buhach being first mixed with enough water to 
make a thin paste and allowed to stand about two hours, after 
which more water is added to bring it to the desired strength, 
the usual proportions being: 2 ounces to 5 gallons of water. 
An alcoholic decoction is also sometimes used. 

Under different trade names, pyrethrum is placed on the 
market in hermetically sealed tin cans, so that it retains its full 
strength until used. Powders that are not packed in tightly 
sealed cans lose their strength, and are therefore less effective. 
In small lots pyrethrum costs 10 cents an ounce; if six pounds 
are purchased it can be had for about 50 cents a pound. 

Tobacco is an old-time remedy for many insects, and still in 
vogue among a certain class of farmers and florists, but in 
recent years it has been largely replaced by other and more 
approved insecticides, such as Paris green and kerosene emul- 
sion, and in greenhouses by the hydrocyanic-acid gas process. 
The method of its application varies according to the crop af- 
fected and the insect. Where tobacco stems and other refuse 
can be easily obtained from the factories it is advisable to use 
it as a protection against certain species of insects. 

For the striped cucumber beetle and melon aphis, it is used 
by sprinkling the hills, particularly when the soil is moist, with 
refuse dust. Thus used it has the advantage of acting as a 
fertilizer and mulch for the plant, as well as being a repellent 
to the beetle- and other insects. Applications must be repeated 
after rainfall. 



INSECTICIDES AND THEIR USES 41 

Nicotine extracts and pozvders are extensively used by florists 
as general fumigants for aphides, thrips, white fly, and other 
small and soft-bodied insects in greenhouses. These extracts 
are manufactured by a number of firms who advertise chiefly 
in florists' journals. They contain a much larger proportion 
of nicotine than decoctions, and are proportionately more ef- 
fective. They are used in various ways: Dry fumigants are 
placed in shallow pans and a few drops of kerosene poured on 
to facilitate ignition. These burn slowly, producing a smudge 
which is fatal to aphides and similar insects. The liquid prep- 
arations are evaporated over an alcohol lamp, or are "painted" 
on steam pipes, or hot irons are put into the receptacles. 

The amount of nicotine solution to use depends upon its 
strength (varying from about 35 to 85 per cent, nicotine), the 
plants to be treated, the size of the frames or greenhouse and 
the construction of the latter, whether tight or loose. A pre- 
liminary test, on a small scale, is therefore a prerequisite to the 
use of a nicotine fumigant. Follow the directions accom- 
panying the preparation used and increase or decrease the 
strength as necessary. If cucumbers are being fumigated, a 
smaller amount may be desirable. One of the most widely 
known of these nicotine solutions has been used with great suc- 
cess at the rate of 5 or 6 teaspoonfuls of the liquid to 8 quarts 
of water vaporized in 5,000 cubic feet of greenhouse space. 
Used thus on cucumbers at night it did not injure the plants, 
while thrips which infested the plants were killed. Aphides 
are more easily killed than thrips, while white flies require still 
longer exposure and repeated applications. 

After treatment plants are carefully syringed with whale-oil 
or similar soap and the house ventilated. A second fumigation 
is sometimes given, allowing the tobacco smudge to remain over 
night. A surplus of moisture is to be avoided, as it induces 
spot, mildew, and similar fungous diseases. 

Sulphur, applied dry in the form of "flowers of sulphur," is 



42 INSECTS INJURIOUS TO VEGETABLES 

a veritable specific for "red spider" on certain plants grown 
under glass. It is also applied dry mixed with an equal bulk 
of air-slaked lime, and by means of a powder bellows. It is 
also used in conjunction with kerosene emulsion or soap washes, 
added in the proportion of I to 2 pounds to 50 gallons of the 
spraying solution. It is first mixed into a paste. As a vapor 
it is exceedingly harmful to plant life, hence should not be used 
as a fumigant in forcing houses or in a confined structure. 

Bisulphid of carbon (CS 2 ), a specific against insects affecting 
stored grain and other products, has a special value in the treat- 
ment of some forms of insects affecting vegetable crops, more 
particularly aphides, and root-feeding insects, such as root-mag- 
gots of cabbage and onion. This reagent, when pure, is a color- 
less liquid and has a powerful and disagreeable odor; it vapor- 
izes rapidly when exposed to the air, is highly inflammable but 
not explosive, and is deadly to all forms of animals, including 
human beings. Its field of usefulness is among such insects as 
we cannot reach with poisons by direct contact or through their 
foods. 

The method of applying bisulphid of carbon varies according 
to the nature of the plants affected and the insects to be de- 
stroyed. The method of treating the melon aphis and root- 
maggots will be described in the consideration of those insects. 

PROPRIETARY INSECTICIDES 

Numerous proprietary insect destroyers are on the market, 
and their number is increasing. Analyses of these are being 
made, with the result that although a few are not without value 
they are as a whole decidedly inferior to approved combinations 
advised by entomologists, of the character that are mentioned 
in preceding pages; in fact, they occupy the same relation to 
standard insecticides that quack nostrums do to the prescrip- 
tions of reliable physicians, or preparation of recognized value 



INSECTICIDES AND THEIR USES 43 

and known composition. 1 Among proprietary insecticides that 
have been reported to be found by analysis of little or no value 
or too costly are those bearing names suggestive of "sure pop," 
"bug shot," "certain death," "kill-em-quick," and certain lice 
and "vermin" exterminators, roach destroyers, etc. 

On this head it is advised that in view of the fact that so 
many proprietary insecticides are either fraudulent or extremely 
expensive, considering the value of their ingredients, it would 
be well to make sure of the composition and value of each 
before purchasing. 

Among the most useful proprietary remedies are nicotine solu- 
tions or tobacco extracts and powders which are not mixtures 
or nostrums, but just what their manufacturers claim for them. 

INSECTICIDE APPARATUS 

In the application of insecticides different types of apparatus 
are necessary, according to whether the material used is to be 
applied dry in powder or as a spray. The types necessary for 
the former are simple, the spraying devices are numerous and 
many efficient sprayers and like mechanisms are on the market. 

For dry application, such as pyrethrum, sulphur, and Paris 
green mixed with flour, powder bellows or atomizers costing 
about $2 are much used, particularly for gardens or where small 
areas in larger fields are infested. 

For spraying. — No stronger evidence of the progress in 
economic entomology could be cited than the number of firms 
engaged in the manufacture and sale of spraying apparatus. 

Such crude mechanisms as are for sale at from 75 cents to 
$2 or $3, both under the title of syringes and sprayers, can 
scarcely be recommended for up-to-date work. They do not, as 
a rule, produce a true spray; they are too apt to get out of 

1 Such as paregoric, Rochelle salts, Seidlitz powders, and various extracts, 
elixirs, tinctures, mixtures, solutions, anodynes, etc. 



44 INSECTS INJURIOUS TO VEGETABLES 

order and therefore do not last longer than a season or two. 
The want of an instrument to fulfill modern requirements for 
a fine spray is met by various manufacturers in the form of 
knapsack sprayers, bucket pumps and barrel spray pumps. 

The spray is obtained by a hose attachment and different 
forms of nozzles, of which the vermorel type is the best. 

The knapsack sprayer is a copper tank made to be strapped 




Fig. 22.— Knapsack sprayer 

on the back of the operator (fig. 22). Within there is a small 
pump which is operated with one hand while the nozzle is held 
in the other. The handle may be removed, if desired, and the 
tank carried by hand instead of on the back. The cost is from 
$9 to $18. It is good for gardens and for moderate-sized plats 
on truck farms. Of its usefulness Mr. M. B. Waite, a 
pathologist of the United States Department of Agriculture, 
says in substance: 

The barrel pump has nearly driven out the knapsack outfit 



INSECTICIDES AND THEIR USES 



45 



in commercial operations. In spraying several acres of can- 
taloupes once the writer was surprised to find that a man with 
a knapsack outfit could do the work at the same price as an 
outfit consisting of a barrel mounted on a sled drawn by a horse 
and operated by three men, one to pump and drive and two to 
carry, the nozzles. The latter outfit, 
however, got over the ground so much 
more rapidly and saved so much time 
that it was mainly used. The 'objec- 
tions to the knapsack pumps are 
numerous. It is hard to get the re- 
quired pressure in the pump on account 
of its small size and instability. It is 
rather heavy to carry on the back and 
is very liable to leak, and the oper- 
ator who can handle one all day with- 
out getting his back wet and some of 
the liquid down his neck is fortunate. 
As a rule, the low pressure obtained 
by the knapsack pump results in an 
inferior job of spraying, though with 
a strictly first-class vermorel nozzle this is not necessarily so. 

Bucket pumps. — Good hand bucket spray pumps of about the 
type shown in figure 23 may be had at from $6 to $7.50. They 
are of great value in the preparation of kerosene emulsion, 
which, as has already been stated (p. 36), should be applied as 
a fine mist-like spray. They may be used with ordinary or 
special buckets and a longer hose than figured (fig. 23) and 
may be necessary. 

Barrel spray pumps. — These are the largest force pumps and 
useful both for the field and orchard. They are mounted on 
barrels or tanks and drawn for field and garden use on wheels, 
so geared as to straddle rows of vegetables, or a narrow sled 
may be made to serve the same purpose. A serviceable sled may 




Fig. 23.— Hand bucket pump 



4 6 



INSECTS INJURIOUS TO VEGETABLES 




Fig- 23x.— Hand barrel spray with cart in operation in a cucumber field 
(After Orton, U S. Dept. Agr.) 

be made by fastening planks across two pieces 2 or 3 x 4 inches 
and with rounded ends for runners. Two-wheeled carts may 
also be used for such an outfit. Such a one designed for spray- 
ing four rows of plants and from two sides at once is used by 
Prof. F. L. Washburn of the Minnesota Experiment Station 
(fig. 24). 




Fig. 24.— A four-row sprayer- (After Washburn) 




INSECTICIDES AND THEIR USES 

Nozzles. — One of the main causes of failure 
on the part of farmers to obtain good results 
from spraying is the use of inferior nozzles which 
are too often supplied by dealers. The ver- 
morel type (fig. 24.x), for sale (single) at about 
$1.25, is the best, having stood the test of 25 
years and more of use. 

Fie. 24* — Vpr- 

REMARKS ON APPLYING INSECTICIDES morel nozzle 

In the application of remedies 12 points are selected as im- 
portant to be observed: 

1. Be sure of the insect which is the primary cause of the 
damage. 

2. Make certain that the best remedy or remedies are used. 

3. When an insecticide is employed, ascertain if it is of 
standard quality, because if it is lacking in strength it will fail 
of its purpose. If not diluted according to directions, and if 
therefore too strong, there is danger of scalding or otherwise 
injuring the plants. 

4. The preparation used should be properly prepared. Thus 
if kerosene emulsion is the remedy, it should be a true emulsion 
and not a mere mixture of water, soap and kerosene. 

5. The best insecticide apparatus for the purpose for which 
it is designed should be obtained, and for vegetables it is nec- 
essary in most cases that a sprayer be used, and as often as not 
the spray must be applied so as to reach the under surface of 
the leaves, and remain on them and not roll off. 

6. The smallest amount of poison should be used to produce 
the desired result ; much poison is wasted by persons who do not 
understand its proper application. 

7. Remedies should be applied at the right time, usually 
when the insect first appears; as, for example, when a cater- 
pillar has just hatched from the egg, or when a beetle begins 
to come out from winter retreats in search of food. Inex- 



48 INSECTS INJURIOUS TO VEGETABLES 

perienced persons apply for information after the principal 
damage is done, and before an answer in regard to remedial 
treatment can be received it is too late to apply remedies. 
In the treatment of insects which may always be expected, for 
example the striped cucumber beetle, preparation should be 
made before the appearance of the pest. 

8. In the case of many insects it is usually necessary to 
apply remedies more than once, sometimes three or four times, 
according to the number of generations of the insects, ancj 
whether severe rains have intervened to wash away applications 
before the insects have fed upon them. 

9. If injury is severe it is often desirable to apply remedies 
for other insects and diseases which may be present, as other- 
wise the crop may be ruined, though the primary cause be re- 
moved. Fertilizers are often advisable to stimulate plants and 
enable the production of a crop in spite of insect injury. 

10. Clean methods of farming are of more value in preventing 
injury than any other method that can be named, and if it were 
more generally observed insect injury would soon be very mate- 
rially reduced. 

11. The cooperation of one's immediate neighbors is very 
desirable in the treatment of many insects, particularly those 
which are not free-flying. 

12. The timely application of a remedy acts as a preventive. 



CHAPTER V 

GENERAL CROP PESTS 

Injurious insects may be classified, as regards the nature of 
their food plants, into several more or less distinct groups. 

The most important of these are choice or special feeders, 
and include many of our worst pests. They attack only single 
crops or crops of a single class, save in the direst necessity 
when they sometimes resort to other crops and weeds. Examples 
of this group are the two asparagus beetles which live exclu- 
sively on asparagus, the cotton worm and boll weevil, which are 
injurious only to cotton, and the tobacco worms which affect 
only tobacco, tomato and plants of the same botanical family. 

Many insects are more or less nearly omnivorous. Although 
some have favorite host plants, they are likely to attack many 
other plants, and when extremely numerous or when the favored 
food becomes scarce they devour nearly every form of vegeta- 
tion that grows in the garden, field, orchard or forest. This 
group is not so numerous as the first and not so destructive, as 
a rule, because of attack being distributed, but certain cutworms 
and other caterpillars, leaf-beetles, flea-beetles, aphides and 
others may do very serious damage, while still others, like 
locusts and army worms, sweep over large areas and in a short 
time ruin entire crops. 

CUTWORMS AND RELATED INSECTS 

Cutworms are among the most troublesome insects with which 
the market gardener has to deal. They are familiar to most 
persons, and sooner or later everyone engaged in plant growing 
has to contend with these pests, for they are what are termed 

49 



5° INSECTS INJURIOUS TO VEGETABLES 

"general feeders," and able to eke out a living wherever they 
may be. Thus it happens that they are to be found in most 
gardens and nearly everywhere else, in pasture land, vineyards, 
fields and orchards, and even in greenhouses. 

The species are very numerous, and many of them, like white 
grubs and wireworms, were the original inhabitants of the soil 
of this country, but some have been supplanted in injuriousness 
by species introduced from abroad. Taken as a class, cutworms 
rank with such insects as the San Jose, scale, Hessian fly, the 
chinch-bug, and others of our worst pests. 

When conditions favor the multiplication of cutworms they 
will feed upon anything green and succulent, whether foliage, 
flowers, buds, fruit, stalks, tubers, or roots. Although nearly 
ubiquitous, they are more especially destructive in truck gar- 
dens, and young, tender plants when first set out, such as 
tomatoes, cabbage, and plants just appearing above the soil, 
such as potatoes and corn, suffer most seriously. Several are 
destructive to foliage of fruit trees, and from their habit of 
climbing, are known as climbing cutworms; while in years of 
unusual abundance, some assume the army worm habit. 

Cutworms are the progeny of owlet moths (fig. 27, c), and are 
nocturnal, remaining hidden during the day to come forth at 
night, the moths to mate and deposit their eggs, the cutworms 
to feast upon whatever happens to be most available and 
palatable. 

There are so many species of injurious cutworms — between 
two or three score — that it is impossible to give a description 
that would fit all, but most common species are robust, soft- 
bodied, smooth or nearly smooth, cylindrical caterpillars, varying 
in color from pale whitish or dirty gray (like fig. 28, a), to near- 
ly black, many being more or less plainly striped or spotted, as 
is the case with the w-marked cutworm shown in figure 25. 

They seldom attract attention except in early spring, and 
then experienced persons can only too readily detect their 




GENERAL CROP PESTS 5 1 

presence by finding young plants with tender stems that have 
just been set out, cut off near the surface of the ground. The 
culprit rests in a curved position during the day concealed in 
the earth around the plants which it has destroyed during the 
previous night. Some species leave open 
holes where they have buried themselves 
in the earth, others seek shelter under 
any debris, such as old boards, stones 
or dead leaves, and a few species have Fig . 25 .- W -marked cutworm 
a habit of dragging portions of plants (Noctua clandestma) 

which they have cut off to their sub- 
terranean retreats where they can feed at leisure. 

Most species are single-brooded northward, but many produce 
two or more generations southward. 

The greatest injury, as previously stated, is done in early 
spring for the following reasons: The last-appearing genera- 
tion of moths issue from the ground in midsummer or autumn, 
and deposit eggs from which larvae hatch and feed until cold 
weather drives them to their winter quarters. A considerable 
proportion of such larvae are from half to three-quarters grown, 
and in this condition many hibernate, although a few species 
pass the winter in the pupal condition and less exceptionally 
as moths. The eggs are deposited, often in large masses, on 
such growth, grasses and weeds as spring up after a crop has 
been harvested, and when this is plowed under to make room 
for the new crop that is planted in spring, comparatively few 
plants come up, and as a result, the immature cutworms are 
forced to feed upon whatever is available. This explains their 
great destructiveness, as it is a matter of yearly occurrence in 
many neighborhoods for cutworms to destroy large portions 
of a planting and even entire crops, necessitating replanting 
sometimes a third or fourth time before a good stand can be 
obtained. 

The life histories of cutworms vary according to the species 



52 



INSECTS INJURIOUS TO VEGETABLES 



and the locality which each inhabits; hence little that is really 
typical of the group can be spoken of in general terms. After 
cutworms have accomplished their customary injuries in the 
spring and have attained full growth, they enter the earth, and 
many species remain in little, rather compact earthen cells 

(fig. 26) for several weeks or even 
months before assuming the pupal 
stage, which is of variable duration 
in the summer, from three to six or 
more weeks before the moths is- 
sue to perform the functions of 
their nature. 

The Greasy Cutworm (Agrotis ypsilon Rott.) is typical as 
regards its general appearance and is abundant in most localities 
suitable to it. It is one of our larger species, measuring when 




Fig. 26. — Pupa of cutworm in 
earthen cell. (After Riley) 




Fig. 27.— Greasy cutworm. 
c, moth. Natural size. 
U. S. Dept. Agr.) 



a, Larva; b, head of same; 
(After Riley & Howard, 



mature about one inch and three-fourths. It is of the dull, 
dirty brown color, characteristic of so many cutworms, with the 
lower surface paler and greenish. The moth (fig. 2J, c) has 
brown fore-wings marked with darker brown, more or less like 



GENERAL CROP PESTS 



53 



the specimen figured, and with an average expanse of an inch 
and three-fourths. It is a cosmopolite. This cutworm has a 
most pernicious cutting habit. It will sever large tomato plants 
over six inches in height generally at an inch above ground, 
and after destroying one plant it travels to others and thus in 
a night a single worm ruins three or four plants. It shows 




s c 

Fig. 28-— Granulated cutworm, a. Larva; /, moth 
Natural size. (After Riley) 

some partiality for cabbage which it frequently devours as fast 
as transplanted. Potato, corn, lettuce and tobacco are favored, 
while ornamental flowering plants are not exempt. Of many 
plants it eats leaves and roots. It is probable that this species 
is double-brooded or has a dual method of hibernation. 

The Granulated Cutworm {Feltia annex a Treitsk.) (fig. 28) 
is brownish gray and similar to the greasy cutworm, but lacks 
the greasy appearance, and may be recognized by the character 
which has suggested its English name. The entire surface of 
the body, as viewed with a magnifier, is seen to be closely 
covered with very small, round, blackish granules, each bearing 
a minute sharp point. The length, when full grown, is about 
an inch and one-half. 

The Variegated Cutworm (Peridroma saucia Hub.). — This 
is with little doubt the most destructive and widely known of 
all cutworms. It occurs nearly everywhere and although, like 
others of its kind, it appears to favor garden plants, it will 



54 



INSECTS INJURIOUS TO VEGETABLES 



attack nearly any form of vegetation, feeding on all parts of 
plants when it occurs in numbers. It is a climbing cutworm, 
and when exceptionally abundant, assumes the army worm 
habit. Its progenitor is a large moth (fig. 29, a) with pale, 
grayish-brown fore-wings tinged with reddish and shaded with 




Fig- 29. — Variegated cutworm (Peridroma saua'a). a, Moth; 
b, larva, lateral view; c, same coiled up; d, dark form, dorsal 
view. (After Howard, U. S. Dept. Agr.) 

darker brown. There is considerable variability in markings, 
which are often suffused. The same holds of the cutworm itself 
(fig. 29, c, d). At maturity this cutworm measures about one 
and three-fourths inches. The variegated cutworm is cosmo- 
politan in the broadest sense of the word, and is injurious 
throughout practically all arable regions. 

METHODS OF CONTROL 

Poisoned baits are the standard remedies against cutworms. 
To be effective they should be applied as soon as attack is 
noticed and are particularly valuable in cases where the direct 
application of poisons is impossible owing to the danger of 
poisoning persons or stock when it is used for food. There are 
two kinds of bait— fresh vegetable and bran mash. 

Vegetable bait. — Vegetable bait may be prepared by spraying 



GENERAL CROP PESTS 55 

a patch of clover, or useless succulent plant with Paris green, 
i pound to 150 gallons of water; mowing it close to the ground, 
and placing it while fresh in small heaps about infested plants 
at intervals of a few feet. Owing to the wilting of this bait, 
in dry, sunny weather, it is advisable to cover each heap with 
a chip, shingle, or something similar. 

Bran mash or bran-arsenic mash is, according to some, still 
more efficacious. Paris green, white arsenic, or other arsenical 
can be used for poisoning, and in its preparation, on account 
of the weight of the poison and the fact that it soon sinks when 
stirred, it is best first to mix the bran with water and sugar 
and then add the poison. The proportions are 2 or 3 ounces 
of sugar or a similar quantity of glucose or molasses to a gallon 
of water and sufficient bran (about a pound per gallon) to make, 
when stirred, a mixture that will readily run through the fin- 
gers. Before planting a crop it is advisable to use bait, and 
for perfect success the ground should be bare, which will have 
the effect of practically compelling the cutworms to feed on it. 

Protection of plants that are set out, such as tomato and cab- 
bage, started under glass, may be secured by placing about the 
base of each a tablespoonful of poisoned bran or a small bunch 
of the poisoned vegetable. Sometimes it is feasible to dip plants 
like tomato and sweet potato in poison before setting out. 
Arsenate of lead is best for this purpose prepared as for spray- 
ing 1 pound to 25 — 50 gallons of water. Where it is possible, 
however, to spray grass or weeds which have grown up in fields 
about to be cultivated, this should be done, as it is an easy 
means for riddance of cutworms and less troublesome than the 
preparation and distribution of baits. Plants may also be pro- 
tected by paper wrappings and tin collars. 

Bordeaux mixture has been tested against the variegated cut- 
worm upon potato vines and asparagus. It was sprayed on as 
a remedy for blight, and it was discovered that plants thus 
treated were free from attack. The use of this, fungicide as a 



5^ INSECTS INJURIOUS TO VEGETABLES 

cutworm deterrent is certainly advisable. In any case, it should 
be employed as a diluent for whatever arsenical is used. 

Hand methods. — On some plants it is next to impossible to 
apply any but hand methods with good results. Experiments 
in Washington State during 1900 demonstrated conclusively 
that in some cases it required less time to shake or brush the 
variegated cutworm from affected plants than to destroy them 
by spraying or otherwise. 

In ordinary cases of cutworms in greenhouses they can be 
held in check by hand-picking. It is the custom of some florists 
to hunt for them at night with a lantern, when they are feeding 
and can readily be discovered and destroyed. 

Treatment as an army worm. — When cutworms assume the 
habit of traveling in armies they should be treated in the same 
manner as advised against the fall army worm in pages which 
will follow. 

The Fall Army Worm (Laphygma frugiperda S. & A.).— The 
fall army worm or grass-worm feeds normally on grasses and 
grains and weeds belonging to the grass family, but will attack 
in its seasons of abundance almost any form of vegetation that 
is encountered in its line of march. At such times it becomes 
a pest in garden and orchard, on lawns and in greenhouses, as 
well as in pastures and in fields of grain. The moth is quite 
unlike that of the common army worm and very variable, there 
usually being two distinct forms, a dull gray and an ornamented 
form (fig. 30, a and b) . The hind-wings are glistening white 
with rosy reflections. The wing expanse is from an inch to. an 
inch and three-eighths. The eggs are deposited in clusters of 
from fifty or more, often in two or three layers. The mass is 
covered with down from the body of the moth. The differences 
between this and the true army worm are shown by figures 30, a, 
30X and 31. 

This insect is undoubtedly native to North as well as South 
America. Its greater abundance in semitropical regions in- 
dicates that it was originally, although not in very recent times, 



GENERAL CROP PESTS 



57 



tropical. At present it is more at home in the South where 
opportunity is afforded for its increase in swamp land, among 
wild rice and rank grasses, but it is also acclimatized in the 
southern portions of the North and appears to be gradually- 
working its way still farther northward. 

Injury has been noted as far north as Chicago and westward 
to Colorado and Montana. 

A feature of this insect's attack, from which it derives its 
name of fall army worm, is that it seldom does appreciable in- 




Fig. 30 —Fall army worm, a, Moth, plain gray 
form; b, fore-wing of Prodenia-like form; c, larva; 
d, abdominal segment of larva; e, pupa, d. Twice 
natural size; others enlarged one-fourth. (Author's 
illustration, U. S- Dept. Agr.) 





Fig. 30x. — a, 
Head ot fall 
army worm; b. 
of army worm- 
Both enlarged. 



jury except in the fall. It is not often noticed, therefore, except 
in the extreme South, earlier than the first of August, while 
the outbreaks of the common army worm usually occur prior 
to that time. 

There is no doubt that there are two or three generations 
produced each year, and each succeeding generation usually 
becomes more destructive. It attacks practically all vegetables. 

The larvae, in years of ordinary abundance, live like cutworms 



58 INSECTS INJURIOUS TO VEGETABLES 

and are so dark and evidently secretive in their nature as to 
usually escape recognition. When, however, an undue increase 
in numbers takes place and the habit of moving in armies is 
assumed, their presence becomes manifest, too late, however, 
in most instances, for remedial treatment. Transformation to 
pupa takes place in little earthen cells, but occasionally pupae 
are not so protected. 

Methods of Control. — In the case of large armies in ex- 
tensive fields, poisons are of little value when outbreaks are at 
their height. When the armies are first noticed the ''worms" 
are as a rule approaching maturity, they have effected much 
damage, and it is difficult at this stage to prevent them from 
passing from one field or other tract to another. It follows 
that, although arsenical poisons are valuable in many cases, we 
must place more reliance in preventives such as cultural and 
mechanical methods. 

In fields of young grain and on lawns many "worms" may 
be killed by crushing with a heavy roller, when the insects are 
at work early in the morning or toward dusk. In fields that 
are injured beyond recovery, sheep or other cattle may be 
turned in in numbers with benefit, as they will kill the larvae 
by trampling upon them. 

Other useful methods of this nature include trenching or 
ditching, or plowing deep furrows in advance of the traveling 
hosts to entrap the larvae which will fall into them, and here 
they may be crushed by dragging logs or pieces of brush through 
the furrows. If 'possible to fill the trenches with water, or if 
they become partially filled by rains, the addition of a small 
quantity of kerosene, so as to form a thin scum over the surface 
of the water, will prove fatal to the "worms." 

Rotation of crops should always be practiced, as well as 
burning over fields when they are too badly infested to recover. 
Above all other precautions necessary to secure immunity from 
attack is that of keeping the fields free from volunteer grain 



GENERAL CROP PESTS 



59 



and wild grasses, since experience shows that these are the 
favorite breeding grounds of the insect; when the larvae hatch- 
ing from these eggs have devoured the grain and grasses they 
are driven to cultivated fields for food. 

Fall plowing and disking should always be practiced where 
circumstances will permit. 

The Army Worm (Heliophila [Lencania] unipuncta Haw.). — 
The true army worm is so well known as a grain and grass 
pest that a short account only need be given, more particularly 
since it seldom injures vegetables other than corn. Its general 
economy closely resembles that of the fall army 
worm, previously treated. The army worm proper 
(fig. 31) is larger, a little stouter, more distinctly 
striped and much smoother than the fall army 
worm, measuring about an inch and a fourth in 
length. The parent army worm is a pale yellow- 
ish brown moth with a white spot near the center 
of each fore-wing. This insect appears much 
earlier in the year than the fall species. From 
May to July it accomplishes its greatest injury; 
and although nocturnal by nature, when conditions 
favor its increase it soon exhausts its food supply, 
crowds then gather and march in armies — the 
habit from which it has received its name — in the 
heat of the day as well as at night. Winter is worm .' A [out 
passed usually in the partially grown caterpillar one-third en- 
state in the same manner as with cutworms. Injury ar§e ' 
may be accomplished by any generation, but is most often due to 
the second brood. 

Remedies are practically the same as advised for the fall 
army worm. 



6o 



INSECTS INJURIOUS TO VEGETABLES 



MISCELLANEOUS CATERPILLARS 

Caterpillars of omnivorous habits other than cutworms and 
webworms may be divided into two groups — naked and hairy 
caterpillars. Both forms are in the main diurnal, at least during 
their early stages, but some naked species as they approach 
maturity crawl into shelter where they are more or less pro- 
tected from the sun's rays as well as from natural enemies. The 




Fig- 32.— Yellow bear, a, Female moth; b y full-grown larva; c, light form of larva, not 
quite mature; d, cocoon; e, pupa. All slightly enlarged. (Author's illustration, 
U. S. Dept. Agr.) 

naked caterpillars are more abundant and injurious, and include 
such species as the zebra and clover caterpillars and corn-ear 
worm. Among the hairy caterpillars are such well-known forms 
as the yellow bear (Diacrisia virginica, figure 32), salt-marsh 
and hedgehog caterpillars and smeared dagger. Most hairy 
caterpillars are rather more abundant on useless plants than on 
crops, a fortunate thing for the grower. 



GENERAL CROP PESTS 



61 



Garden Webworm (Loxostege similalis Gn.). — This species 
affords an excellent example of an insect that feeds normally 
on weeds and only in times of abundance becomes a pest and 
general feeder. In such times it will attack most vegetables. 
In 1885 a serious outbreak occurred over a large area in Kansas, 
Nebraska, Missouri, Arkansas, Texas, and in what was then 
known as Indian Territory. Corn suffered most and a replanting 




Fig. 33.— Garden webworm. a, Male moth; b, larva, lateral view; c, larva, dorsal view; 
d, anal segment; e, abdominal segment, lateral view; /, pupa; g, cremaster. (After 
Riley, except c, Chittenden, U. S. Dept. Agr.) 

was necessary in several instances, and the yield per acre was 
much reduced, owing largely to the ravages of this webworm. 

The moth (fig. 33, a) is variable, yellow, buff, or reddish- 
brown. It has an expanse of wing of about three-quarters of 
an inch. The larva (6, c) varies also, the ground colors run- 
ning through pale and greenish yellow to dark yellow. It is 
strongly marked with black, piliferous spots (d, e). 

The garden webworm occurs generally throughout the United 
States and is most injurious in the South. Its favored natural 
food plant is "careless" weed (Amaranthus). The caterpillar, 
soon after hatching, draws together the edges of a leaf by 
means of its web, or fastens together two contiguous leaves, 
forming a shelter, from which it crawls forth to feed. 

Remedies. — A spray of Paris green has been used with per- 
fect satisfaction against this webworm, the fact that it is more 



62 INSECTS INJURIOUS TO VEGETABLES 

or less surrounded by webs and leaftissues offering little or no 
barrier to the effects of the poison. In addition, clean cultural 
methods, including late plowing in the fall followed by deep 
plowing in spring, and the^ burning of all waste material and 
weeds, are of service in controlling this pest. Early planting is 
useful as a safeguard for some crops. 

LEAF-BEETLES 

Leaf-beetles (Chrysomelidce) are among the most important 
groups of insects, economically speaking. Many of them select 
•in the larval stage single species or plants of the same or 
similar botanical families, but the beetles are more inclined to 
be omnivorous, and some devour nearly all forms of vegetation. 
Their larval habits are variable, but a considerable proportion 
subsist on plant tissue on the external surface of leaves. A 
smaller number develop in mines which they construct in the 
leaves or in the roots, in fruits and seeds, and even in flower 
heads and in stems. A familiar example of a leaf-beetle larva 
that lives externally on leaves is the Colorado potato beetle, and 
of the root-feeders are the corn root-worms. An example of 
those which live in seeds is the twelve-spotted asparagus beetle. 
Such as feed on the outer surfaces of leaves are more or less 
grub-like, with six true legs and a proleg at the posterior ex- 
tremity. Their colors are often well marked, red or yellow, 
with rows of black spots as in the case of the Colorado potato 
beetle. The root-feeders, however, are pale, frequently white 
and elongate, even threadlike in form. 

The greatest amount of injury is generally due to the hiber- 
nated beetles on young and tender plants before they have made 
good growth. Some species, indeed, cause little trouble after 
this period, while others, like the Colorado beetle, occasion 
losses of greater or less extent throughout the growing season 
of the plants which they affect. 

Our most common omnivorous leaf-beetle is the twelve- 



GENERAL CROP PESTS 63 

spotted cucumber beetle (fig. 3), the parent of the southern 
corn root-worm. It will be considered more at length in the 
chapter on corn insects. 

FLEA-BEETLES 

Flea-beetles (Halticini) constitute a sub-family of the leaf- 
beetles. They are of elongate oval form and similar color, 
frequently striped like the cucumber beetle, and may be dis- 
tinguished by their enormously developed hind thighs, which 
furnish them with powerful leaping ability. The most injurious 
forms are minute and dark-colored. Their habit of suddenly 
hopping from the vegetable on which they are feeding has given 
them the common name of flea-beetles or fleas, some species 
being known as "potato flea," "cabbage flea," etc., according to 
the plant infested. Many flea-beetles are general feeders, and 
nearly all are subject to a periodicity, dependent on factors with 
which we are little acquainted, but doubtless in large part 
traceable to atmospheric conditions, moist weather furnishing 
the best conditions for the development of the young or larvae, 
and dry weather being inimical to their increase, this hypothesis 
being based upon the knowledge that the larvae of many species 
are subterranean. 

Injury is frequently very severe on young plants and is due 
in the greatest measure to the ravages of the adult flea-beetles 
which frequently appear in prodigious numbers in cultivated 
fields and like a pestilence sweep everything before them, their 
depredations often necessitating the replanting of entire crops. 

The larvae of most flea-beetles develop in weeds, a compara- 
tively small proportion living on cultivated crops. Knowledge 
of this fact is of value in indicating methods of control. 

The Pale-striped Flea-beetle (Systena blanda Mels.) is a de- 
structive vegetable-feeding species. It measures about an 
eighth of an inch, is cream-colored, with nearly black abdomen 
and eyes, and the wing-covers are ornamented with a bright 
sutural and two narrower marginal stripes of dull light brown 
(fig. 34, b). The larva is white and slender, with light brownish- 



64 



INSECTS INJURIOUS TO VEGETABLES 



yellow head. The legs end in blunt padlike processes. It is an 
American species and of rather wide distribution, from New 
Jersey southward to Georgia and westward to California. The 
beetle is nearly omnivorous and injurious to beans, beets, po- 
tatoes, tomatoes, eggplant, corn, carrot, melon and other cucur- 
bits., turnip and other crucifers. It also attacks strawberry, 
cotton, oats, peanuts and the leaves of pear. The beetles some- 
times do severe damage in three or four days. The species 
hibernates as a beetle, and appears in the vicinity of the District 



# 




Fig 34 —Pale-striped flea-beetle, a-. Larva; b, beetle; c, eggs; d, sculpture ef egg; 
e. anal segment, from side: /, same from above, a-d. six times natural size; e, f, much 
enlarged. (Author's illustration, U- S. Dept. Agr.) 



of Columbia early in June; egg laying continues to the middle 
of July, if not later: injury is usually due to the beetles upon 
their first appearance and almost any valuable crop may be 
injured. The larvae live below the ground, and have been ob- 
served by the writer and others feeding on roots of corn, lamb's- 
quarters and Jamestown weed. 

The Banded Flea-beetle (Systena tccniata Say). — The banded 
flea-beetle has similar habits to the preceding and similar struc- 
ture ; it was in fact, until quite recently very generally confused 
with the pale-striped form, and many references to injuries by 
it are reallv due to the latter. Like the latter it varies con- 



GENERAL CROP PESTS 65 

siderably. It is polished black with white stripes. A common 
dark form is shown in figure 35. 

METHODS OF CONTROL 

Arsenicals and Bordeaux mixture. — The best remedies for 
leaf-beetles and flea-beetles are Paris green or other arsenical 
and Bordeaux mixture, either in combination or separately. 
Bordeaux mixture alone acts as a deterrent, and the writer sug- 
gests that instead of using either one separately, or both in 
combination, that the greater portion of an infested field or 
garden be sprayed with the Bordeaux mix- 
ture freely and as often as may be nec- 
essary, particularly after heavy rains. 
while strips here and there be sprayed ex- 
clusively with Paris green. This will 
have the effect of driving the beetles from 
the Bordeaux-sprayed plants to the poi- 
soned ones. Paris green alone, dusted dry 
on infested plants, is thoroughly effective 
against many species. Arsenate of lead 

' . . Fig. 35. — Banded f.ea-bestle, 

is preterable tor spraying tender d^^ety. (Author's u- 
plants like beans,, whose foliage is lustration. U.S. DeptAgr.) 

liable to scorching. Plants like to- 
mato, eggplant, and cabbage that are started under glass and 
that are liable to flea-beetle attack, should be dipped in a 
solution of Bordeaux mixture and Paris green or lead arsenate 
before transplanting. For direction see page 55.. 

Kerosene emulsion and soap washes, even strong soap-suds, 
have been used with profit in combating some flea-beetles. 

PyretJirum. dry. mixed with flour or road dust, may be em- 
ployed for small gardens. 

Cultural methods. — In the protection of young plants knowl- 
edge of the fact that the larvse of many species subsist by 
preference on weeds must be remembered, and the grower 
should, moreover, familiarize himself with the particular natural 




66 INSECTS INJURIOUS TO VEGETABLES 

or wild food of the beetles which injure his crops. Thus night- 
shade and Jamestown weed harbor the larvae of the Colorado 
beetle and flea-beetles which attack potato and eggplant, and it 
is therefore imprudent to plant crops in fields which have 
produced such weeds. Injury to corn by corn root-worms is in 
many cases directly traceable to planting in corn land, and flea- 
beetle damage to corn follows when this crop is grown in soil 
previously in grasses which furnish food for their larvae. In 
the same manner leaf-beetles and flea-beetles which attack beans 
and beets, breed in such common weeds as lamb's-quarters. 

At the same time that beetles are ravaging our crops, they 
may also occur on nearby weeds, and for thorough work the 
insects should be destroyed by poisons or other means on the 
wild as well as the cultivated plants. 

Poultry and toads are fond of leaf and flea-beetles, and it 
is recommended to encourage these valuable aids to the farmer, 
by placing coops of chickens or other young fowl in vegetable 
gardens and to protect the toads. 

BLISTER BEETLES 

Many species of blister beetles (Meloidce) are very destructive 
to vegetables, particularly in the Southwest, and especially to 
potatoes and beets, beans, peas, and other leguminous crops. 
They are gregarious and in their season habitually congregate 
in great numbers. Some have the migratory habit, feeding 
voraciously, running with great rapidity, and flying from time 
to time. Thus it happens that they frequently descend in such 
numbers on a field that a crop is ruined in a few days, when 
the insects go elsewhere or disappear and are perhaps seen no 
more until the following year. After the departure of one 
species of blister beetle another frequently follows, to be re- 
placed sometimes by a third. Blister beetles are not an unmixed 
evil, however, since they do some good in their larval stage to 
compensate for the harm the beetles occasion to our crops. 



GENERAL CROP PESTS 



67 



Their larvae destroy grasshopper eggs and thus aid in keeping 
these pernicious insects in check. This is especially true where 
both blister beetles and grasshoppers abound. But the benefits 
derived are really more than counterbalanced by the losses oc- 
casioned by the rapacity of the beetles; hence measures should 
be employed to destroy them when they occur in harmful num- 
bers. Blister beetles are apt to be found in practically all veg- 
etable fields. 

The Striped Blister Beetle (Epicauta vittata Fab.). — Before 
the advent of the Colorado beetle this was considered the most 



v / 





Fig. 36- — Striped blister 
beetle (Epicauta vittata). 
Female beetle. (Author's il- 
lustration, U. S. Dept. Agr.) 



Fig. 37.— Three-lined blis- 
ter beetle (Epicauta lemni- 
scata). (Author's illustration, 
U. S. Dept. Agr.) 



destructive potato pest of the East and, probably because it is 
striped somewhat like the latter, it is more often called "old- 
fashioned potato bug" than other species. It can be easily 
identified by means of the illustration (fig. 36). Although much 
attached to the potato, this species also does injury to beets, 
beans, peas, tomatoes, radishes, and melons. 

The Three-lined Blister Beetle {Epicauta lemniscata Fab.). — 
This blister beetle very closely resembles the preceding; in fact, 



68 



INSECTS INJURIOUS TO VEGETABLES 



the two are frequently confounded, and injuries inflicted by one 
attributed to the other. The form under consideration (fig. 37) 
is a little more slender, has three stripes on each wing-cover 
instead of two, and is a little longer. It is very abundant south- 
ward, and is partial to potato, cabbage, squash, and to beet tops. 
The Spotted Blister Beetle {Epicanta maculata Say). — The 
southwestern portion of the United States is the home of many 
species of blister beetles not found in 
the north and east. Among the most 
abundant is the species illustrated in 
figure 38. Its body is covered with 
fine gray hairs, with small areas on 
the elytra, through which the natural 
black of the body shows, giving it the 
appearance of a gray insect finely 
dotted with black. It abounds from 
Texas and New Mexico northward to 
South Dakota, thence westward' to 
California and Oregon. It is found 
upon potato, beet, clover and other 
plants. 
Remedies. — Paris green is one of the best remedies for blister 
beetles when they occur on potatoes and most other crops. It 
may be applied dry, or as a spray, according to directions al- 
ready given in the discussion of insecticides. Arsenate 
of lead is also excellent for these pests. Repeated ap- 
plications are sometimes necessary, since the poisoned beetles 
are replaced by others. A remedy employed with success in 
the West consists in sending a line of men and boys through 
infested fields to drive the beetles, by short flights and running, 
before them until they alight in windrows of hay, straw, or 
other dry vegetable material which have previously been pre- 
pared along the leeward side of the field. When the beetles 
have taken refuge in such a windrow, it is fired and the beetles 




Fig. 38.— Spotted blister 
beetle. (Author's illustra- 
tion, U. S. Dept Agr.) 



GENERAL CROP PESTS 6q 

are burned. Whatever remedy is employed should be applied 
at the outset of attack in order to be of substantial value. 



GRASSHOPPERS AND RELATED INSECTS 

Of great importance in the West, and in some seasons in other 
regions, are numerous species of locusts, or short-horned grass- 
hoppers. Several related insects, such as katydids and crickets, 
are also injurious. All of these are general feeders, and as a 
rule destructive to vegetable crops only in seasons which have 
been particularly favorable to their multiplication. The num- 
bers of species of these insects mount into the hundreds, but 
the most important forms might be reduced to a double score. 

For present purposes it will be necessary to mention only a 
few of the most abundant forms. Grasshoppers are mostly 
large insects, with mouth-parts formed for biting, with young 
more or less closely resembling the adults, save for the lack of 
wings. Their name is sufficient indication of their habits: they 
live normally in grasses, and their hind thighs are enlarged 
for leaping. Everyone knows them so well that further descrip- 
tion is unnecessary. Some species are capable of extended 
flight for hundreds of miles with intermissions of daily stops 
for food. At such times they occur in swarms, and sometimes 
darken the face of the sun, or at night of the moon. 

Grasshoppers may be classified in regard to their habits as 
non-migratory and migratory. In the latter group are our com- 
monest species which breed and pass their entire lives in or 
near the place where the eggs were laid from which they de- 
velop. The migratory species develop in enormous numbers, 
and when they become too abundant for the food supply of the 
region where they originated they migrate. They are most 
troublesome in arid and semi-desert regions, and their numbers 
are subject to variation according to climatic conditions and 
locality. Dry regions are liable to the visitation of a locust 



70 



INSECTS INJURIOUS TO VEGETABLES 



swarm at any time of the year, and they are the most dreaded 
of pests, because of the rapidity of their attack, when they lay 
waste large districts, and even considerable portions of states. 
The Red-legged Locust (Melanoplus femur-rubrum DeG.). — 
This is our commonest North American grasshopper, being 
found practically everywhere. It is one of the smaller species 
(fig. 39), and where it is not held in subjection by natural 

enemies it may become a de- 
cided nuisance in cultivated 
lands. It seldom exhibits the 
migratory tendency, but some- 
times gathers in swarms and 
moves in concert, not, however, 
rising to great heights, but drifting with the wind as do the true 
migratory species. 

The Rocky Mountain Locust (Melanoplus spretus Thomas). 
— This is the most destructive of all native grasshoppers, and 
has been the cause of greater "losses to agriculture in the past 
than perhaps all of the other known species of grasshoppers 




Fig 39. — Melanoplus femur-rubrum 
Natural size. (After Riley) 




*6 "~ •*"'~-*»^^ , '^i^i£=^£|EES5F : " 

Fig. 40 — Rocky Mountain locust, a, a, a, Female ovipositing; b, egg-pod extracted 
from ground, with end broken open; c. a few eggs lying loose on ground; d, e, 
earth removed, to illustrate egg-mass in place and one being placed;/, where a mass 
has been covered up. (After Riley). 



GENERAL CROP PESTS J I 

combined. Its range of injuriousness is not limited to the Rocky 
Mountain region, but it is more abundant there than elsewhere. 
It is illustrated in figure 40. Those who were interested in 
farming in the 70's in Kansas, Nebraska, and some neighboring 
states have cause to remember the depredations of the Rocky 
Mountain locust. During 1874-1877 it was directly responsible 
for the loss of $100,000,000, in addition to an indirect loss by 
the stoppage of business and other enterprises which might 
have aggregated as much more. It was for an investigation of 
this species that the United States Entomological Commission 
was formed, which published from 1877 t0 l &79 two voluminous 
reports on it alone. 

The Differential Locust {Melanoplus differ entialis Thomas).— 
In the Middle West the farmer is much bothered at times by 




Fig. 41.— Melanoplus differentialis- Natural size 
(After Riley) 

the large yellow locust, shown in figure 41. It is found along 
roadsides and on the edges of groves, preferring rank vegeta- 
tion where such abounds. When it becomes unusually numer- 
ous it is quite destructive to vegetable crops and to cereals. 

METHODS OF CONTROL 

Locusts or grasshoppers are largely kept within normal num- 
bers by numerous enemies, among which are many large forms 
of insectivorous birds and mammals, batrachians and reptiles. 
They also have large numbers of predaceous and parasitic insect 
enemies, which kill them off in ordinary seasons. With changes 
of the weather, however, the insect enemies are frequently de- 
stroyed, and then the locusts become abundant. In such cases 



>]2 INSECTS INJURIOUS TO VEGETABLES 

the grasshoppers can be controlled by several artificial methods. 
The remedies that have proved most efficient are plowing under 
the eggs before these have had time to hatch, and the capture 
by means of hopper-dozers of the unfledged locusts, as well 
as many of those which have become winged. These are shallow 
sheet-iron pans in which are placed tar or coal-oil tar or kero- 
sene oil, and which maybe drawn or pushed by hand over the 
ground or by horses, in such a manner that the hoppers will 
leap into the pans and be killed by coming into contact with 
the tar or oil. Hopper-dozers are shown in figures 213; and 2i#. 

Other remedies of great value in the prevention of injury to 
our cultivated crops are the bran-arsenic mixture and poisoned 
horse droppings. Directions for preparing the former have 
been given on page 54. 

Poisoned horse droppings consist of 1 part of Paris green 
mixed thoroughly in 60 parts of fresh horse droppings, 2 pounds 
of salt to half a barrel of mixture being added after being dis- 
solved in water. This is placed in half barrels and drawn on 
carts to the edge of the infested field or one likely to be invaded. 
The mixture is then scattered broadcast along the edge of the 
crop, or wherever needed, by means of a trowel or wooden 
paddle. The locusts are attracted to it and are killed in large 
numbers by eating the poison. Although this mixture is "sure 
death," it sometimes requires from two to five days for it to 
kill the locusts. 

Turkeys are of great value in freeing orchards and vine- 
yards of locusts, and they may be employed in other fields for 
the same purpose. In one case a flock of 766 turkeys were kept 
at work in the destruction of grasshoppers. The turkeys have 
to be watched, as they sometimes vary their diet with vegetables. 

In some cases it has been possible to ascertain the particular 
breeding places of grasshoppers, some species depositing their 
eggs in pasture lands and among foothills at the bases of 
mountains in the Far West, in regions in which the tar weed 



GENERAL CROP PESTS 73 

grows. Here the eggs can be destroyed by burning over the 
ground late in the fall after all of the eggs are deposited, or 
by plowing them in to a depth of six or eight inches before 
they hatch in the spring. 

In case it is for any reason not feasible to employ any of 
these last mentioned remedies, and the place of egg deposit is 
ascertained, a watch should be kept for the young grasshoppers, 
and they should be destroyed as soon as possible after hatching 
by means of bran-arsenic mash. 

Cooperation is greatly desirable in the treatment of grass- 
hoppers, particularly in regions where they reach their greatest 
development; and the thoroughness with which work is done 
in one year will show the next season in the greatly reduced 
numbers with which the farmers will have to deal. 

Remedies for grasshoppers in general are applicable to the 
migratory species, but the latter sometimes occur in such im- 
mense swarms that it is difficult to treat them. It is of the 
highest importance that whatever remedies are employed must 
be used at the very first onset and generally over considerable 
territory, as the insects fly from one field to another. 

WHITE GRUBS 

White grubs occupy a prominent position among the many 
insect foes to agriculture. There are several hundred distinct 
forms of these creatures, each representing a different species 
of the family Scarabaeidae. A considerable number are of prime 
importance economically, the remainder are less injurious or 
do not attack useful plants. The noxious forms subsist on 
roots and are very abundant under sod, and in similar locations. 
Of these a considerable majority of the typical white grubs 
belong to the genus Lachnosterna, of which nearly a hundred 
species are known. 

The parents of white grubs are known as May beetles or 
"May bugs" in the South and Middle states, and as June beetles 



74 INSECTS INJURIOUS TO VEGETABLES 

or "J une bugs" in the North, from their occurrence in numbers 
in these months in these different regions. Injury is by no 
means confined to the white grubs, but can often be laid to the 
account of the beetles, but the latter are most destructive to 
shade and fruit trees. 

White grubs or "grub-worms," with wireworms and cutworms 
were the original inhabitants of the soil before the advent of 
civilized man. They lived in our open prairies when America 
was still a wilderness, and they continue to dwell in our grass 
lands, meadows, fields and gardens and repel all attempts toward 
their permanent removal. The farmer who imprudently plants 
corn or potatoes in fields that have long laid waste and become 
grown up with weeds and grasses, or where strawberries have 
been the previous season, does so at the risk of losing his crop. 
The problem of how to. destroy them and to protect the crops 
from their ravages is a subject requiring constant and scientific 
treatment. Injury appears to be most noticeable to corn, 
grasses, small grains, beets, potatoes and other root crops, and 
strawberries, but the roots of young shade, fruit and forest trees 
are also attacked. 

As with insects of similar habits, white grubs and May 
beetles are liable to considerable fluctuation of numbers in dif- 
ferent localities and years. This is most noticeable after crop 
rotation, particularly, as might be inferred from what has al- 
ready been said, where susceptible crops are planted in grass 
lands. Attack may commence from the time the plant sends 
out roots, and continue for a much longer time, as these insects 
pass two or three years from the egg until they reach the adult 
condition. When the larvae are present in great numbers at 
the roots, the plants soo« die and whole crops are ruined. 

In a general way white grubs may be described as large, soft 
white or yellowish grubs, with wrinkled bodies, sparsely covered 
with fine hairs, having yellowish or brownish heads with strong 
mandibles, three pairs of distinct legs on the fore part of the 



GENERAL CROP PESTS 75 

body (the three thoracic segments) and the hinder portion of 
the body considerably thickened toward the end. The normal 
position of typical white grubs is curved, as shown in figure 42, e. 
They crawl on their sides, not on their backs as is the case with 
the non-injurious white grub of the June beetle. 
The parents of the injurious or typical white grubs (Lach- 




Fig. 42.— Arcuate May beetle, a, Beetle; b, pupa; c, egg; d, newly-hatched larva; e, 
mature larva; /, anal segment of same. (Author's illustration, U. S. Dept. Agr.) 

nostema spp.) are for the most part large, shining brown beetles, 
known to every one from their habit of flying into lighted 
rooms through open windows, in late spring and early summer, 
buzzing and bumping upon the ceilings and walls and finally 
falling to the floor. A comparatively small number are yel- 
lowish, or plum color, and some few are nearly black. 

From April to July, according to climate, these beetles appear, 
often in great numbers, about our electric lights and upon our 
fruit and shade trees, their appearance each day beginning al- 
most uniformly at sundown. They feed voraciously upon the 
leaves of trees, and bushes such as blackberry, but are especially 
fond of the foliage of nursery stock and other young trees, 
particularly oak, chestnut, hickory, maple, and fruit trees, often 
doing such damage to newly transplanted shade and orchard 
trees as to result in their complete defoliation and destruction. 
The beetles fly and feed only at night, and during the day 
remain perfectly quiet in the vicinity of their feeding places. 
It has lately been shown conclusively (what was previously in- 



76 INSECTS INJURIOUS TO VEGETABLES 

ferred by deduction) that one species, Lachnostema arcuata, 1 
requires only a little over two years for larval development, but 
about three years are consumed from the time the egg is laid 
until the appearance of the beetle above the ground, and this 
is probably true of most of the species which occur in this 
country. Thirteen days was ascertained as the egg period, 
twenty-three for the pupa, and the total period from egg to 
adult required two years and fifty-one days. 

The sexes pair soon after their first appearance and the 
females enter the earth for oviposition. The eggs, which are 
rather large and whitish or gray, are deposited singly in the 
ground. The grubs, hatching among the roots of grass and 
similar plants, feed at first upon the tender rootlets and after- 
ward on the larger roots, and slowly increase in size until mature. 

The species which have been observed usually transform to 
pupae from the middle of June to September of the second or 
third year after hatching, and become fully-developed beetles in 
August or September of the same year. They remain in the 
earthen cells in which transformation has taken place, some- 
times at a depth of from twelve to eighteen inches, where they 
are protected from cold and frost, and appear abroad the fol- 
lowing spring to repeat the life cycle. Hibernation may occur 
in two stages of the larva, and occasionally in a third, and as 
beetles. 

The Arcuate May Beetle {Lachnostema arcuata Sm.) is the 
common May beetle of the Middle Atlantic region. The North- 
ern June Beetle (Lachnostera fusca Frohl.) is abundant in the 
Middle Atlantic region, and is quite as destructive and over 
a wider extent of territory. It is the common species from 
New England to Illinois, and occurs, but comparatively rarely, 
farther west. A large proportion of the injury caused by white 
grubs and June beetles in the region specified are due to this 
insect. 

1 See article by the writer, Bui. No. 19, Div. Ent., U. S. Dept. Agr., pp. 74-80. 




GENERAL CROP PESTS J J 

The winged Northern forms of May beetles are replaced in 
Texas and some other portions of the South by three common 
species, two wingless (Lachnosterna cribrosa Lee. [fig. 43] and 
L. lanceolata Say) and one with similar habits (L. farcta 
Lee.) which do great damage in their beetle stage to trucking 
industries. They subsist largely upon 
weeds, hence in addition to treating af- 
fected plants with arsenicals, the weeds 
should be similarly treated. Late fall or 
winter plowing and avoidance of weedy 
fields for planting are advisable as pre- 
ventives. Swine should be used for de- 
stroying them and on small areas hand- 
picking can be employed, when the beetles Fig . ^,- Lachnosterna crib . 
make their appearance an hour or more rosa - Female. (Sander- 

, r , son, U. S. Dept. Agr.) 

before sundown. 

Among white grubs that are likely to be mistaken for the 
more injurious forms {Lachnosterna spp.) are the carrot 
beetle, which will be considered in a later chapter; the "muck 
worm," which occurs in manure and in the droppings of cattle, 
and which appears to be normally a purely dung-feeding 
species; the sugar-cane beetle; the rice grub; the green June 
beetle, and the brown fruit-chafer, which last will be described 
in the consideration of insects affecting sweet corn. 

PKEDACEOUS AND PARASITIC ENEMIES 

Although white grubs are apparently protected by their sub- 
terranean mode of existence and their life, as beetles, is com- 
paratively brief, many predatory animals as well as parasitic 
and predaceous insects attack and destroy them. Birds of sev- 
eral species and most wild mammals which still linger in cul- 
tivated regions are among this number. Domestic fowls are 
very fond of white grubs and, when given the opportunity, fol- 



78 INSECTS INJURIOUS TO VEGETABLES 

low the plow for them. Swine also search out and eat many 
which they obtain by uprooting the turf. 

Of the insect enemies of white grubs are Tachina flies, wasps 




Fig. AA.—Tiphia inornata- Parasite of white grub, a, Female wasp; b, head of 
larva; c, larva from below; d, cocoon cut open. (After Riley) 

and parasitic Hymenoptera, mites, and predaceous ants.- Among 
these insects is the wasp, Tiphia inornata (fig. 44). Under 
certain conditions white grubs are also much subject to infec- 
tion by fungous parasites. 

REMEDIES FOR WHITE GRUBS 

Insecticides. — Good results have followed the use of bisulphid 
of carbon and kerosene emulsion against some species. The 
emulsion is diluted about ten times and poured on the ground 
about the infested plants. Application is made just before rain- 
fall, to insure the emulsion being washed deep into the soil so 
as to come into direct contact with the larvae. If rain does not 
fall within a day or two a copious watering should follow the 
application. Gas lime is also valuable. (See page 34.) 

Fall plowing is a most effective remedy. The land should 
be thoroughly broken, and loosened to expose the grubs and 
beetles to the elements during winter. This is particularly 
valuable in cold climates, as white grubs are unable to with- 
stand exposure to severe frost. Cross-plowing is sometimes 
advisable where there is severe infestation. This will insure 
the ground being often disturbed, and, if kept clean of weeds 
and other vegetation, the grubs can be "wiped out." 

Preventive measures are still more valuable. The best of 



GENERAL CROP PESTS 79 

these consists in avoiding for the planting of vegetable crops 
land which is already known to contain white grubs and espe- 
cially grasslands, whether meadow or prairie. Corn fields should 
not be planted to root crops and the like without rotation with 
clover or other immune crops. Summer fallowing of infested 
land is said to be useful. 

Rotation of crops is valuable in connection with fall plowing. 
In case infested land is desired for the planting of corn, beets, 
potatoes, or other crop subject to severe injuries by white grubs, 
an application of fertilizer, such as nitrate of soda or kainit, 
put on as a heavy top dressing after the ground is prepared and 
before planting, has proved of benefit in some cases. 

Domestic animals. — Much good may be accomplished by en- 
couraging domestic fowls to follow in the furrows to pick up 
the grubs as they are turned up by the plow. Hogs are also 
exceedingly fond of white grubs, and if allowed the run of 
localities where these are abundant, after the crop is made, they 
will root up the ground and devour great numbers of them. 

WIREWORMS 

Of similar importance to white grubs as general farm pests 
are the wireworms. Though not related to the white grubs, 
they have very similar habits, the injurious vegetable-feeding 
forms being strictly subterranean and subsisting at the expense 
of various crops, especially corn, cereals, and grasses, but at- 
tacking, in the absence of these, various vegetables and other 
plants. The subject of soil and environment as regards attack 
by wireworms has not been thoroughly studied, but certain 
species are more numerous in sandy lands, and others are almost 
always found in unbroken prairies and in wild grasses. Thus 
it happens that, as in the case of white grubs, injury is most 
apt to occur when corn and other vegetables are planted in old 
sod, along the borders of marshes, in pastures and meadows. 

Nearly every tiller of the soil is familiar with wireworms, 



8o 



INSECTS INJURIOUS TO VEGETABLES 



and there are many species, but, fortunately, a small percentage 
only of nearly 600 described forms have been identified in con- 
nection with losses. From an agricultural viewpoint they fall 
into two classes, such as feed upon living vegetation, and those 
which subsist upon rotten wood and similar material. Most of 
the noxious forms that have been recognized are wire-like, 
hence the common name, and are nearly cylindrical, hard, 

smooth and shining, and of 
a yellowish or reddish color. 
They have three pairs of 
legs placed far forward on 
the anterior extremity, and 
the last segment (the thir- 
teenth counting the head) 
ends in a proleg on the un- 





Fig. 45.— Wheat wireworm. a, Beetle; b, 
larva; c, anal segment of larva in profile. 
(Author's illustration, U. S. Dept. Agr.) 



Fig. 46. — Common click- 
beetle. Three times natural 
size. (After Forbes.) 



der surface. They are surprisingly hard in texture and among 
the most vigorous insects known, being difficult to poison by 
means of anything that has been tried. A common and destruc- 
tive species known as the wheat wireworm (Agriotes mancus 
Say) is illustrated by figure 45. 



GENERAL CROP PESTS 8l 

Wireworms are the offspring of snapping or click beetles 
or "snap-bugs," which are rather hard, pubescent creatures of 
elongate, oval form, and readily distinguishable from any other 
insects by the habit from which their common name has been 
derived, of vaulting into the air with a sudden click when they 
happen to fall upon their backs. The common click-beetle 
(Melanotics communis Gyll.) is shown in figure 46. 

Of the various vegetable crops attacked potatoes, according to 
record, are most injured, by having the surface of the tubers 
gnawed into and eroded by the worms." Turnips suffer similar 
injury, as do also to a less extent carrots, beets, cabbage, onions, 
lettuce, and others. In attacking growing plants wireworms 
usually devour the smaller roots or tender tubers, according to 
the plant affected, and in the case of attack on corn they fre- 
quently kill the plant by boring cylindrical channels through 
the under-ground portions of the stalk. 

The life histories and habits of wireworms vary according 
to species and climate, but in many respects they resemble the 
white grubs so closely that details may be omitted. 

The Cornell University experiment station carried on, through 
Messrs. Comstock and Slingerland, a valuable series of experi- 
ments against these pests extending over three years, with the 
result that none of the alleged standard remedies produced 
satisfactory effects. In short, the results were negative rather 
than positive, and no single method has yet been devised by 
which we can destroy these insects as we can most other pests. 
This is due to natural causes — viz., to the hardness and con- 
sequent hardiness of wireworms, two qualities which go hand 
in hand as regards insects and which render these creatures 
almost impervious to poisons that would destroy other insects, 
and to the fact that they live during nearly their entire active 
stage as wireworms usually rather deeply in the soil. They 
require two or three years, like the white grubs, for full matur- 
ity from egg to adult. 



82 INSECTS INJURIOUS TO VEGETABLES 

METHODS OF CONTROL 

No application that can be made to the soil will kill the wire- 
worms without, at the same time, rendering the land unfit for 
cultivation for some time afterward. 

Most remedies, preventives, repellents and poisons that have 
been tried are hardly more than palliative. From among these 
the ones that give most promise are early fall plowing, the use 
of poisoned baits early in the season, with the selection of un- 
infested land for planting, and rotation of crops. We are in 
fact confronted with much the same problems as in the treat- 
ment of white grubs, only wireworms are even more difficult 
of suppression. 

Selection of land for planting. — The most important of de- 
fensive methods is the selection of the land for planting. 
It is inadvisable to plant crops peculiarly subject to wire worm 
attack, such as corn, potatoes, and other vegetables, as well as 
cereals in sod land or in unbroken prairie, and it is equally 
unwise to cultivate such crops in fields in which wireworms 
are known to be present. 

Fall plowing. — Infested or "suspicious" soil should first be 
prepared for the crop by plowing early in the fall. By this 
process the cells in which the pupae and hibernating adults are 
resting are broken up and the insects destroyed in great num- 
bers, so that fewer individuals survive to deposit eggs for an- 
other generation of wireworms the following year. Such as 
are not destroyed outright by this method will be more exposed 
to the elements and to predatory enemies. 

Crop rotation should also be practiced in the same manner 
as prescribed for white grubs. In addition to clover, buckwheat 
is said to be a valuable alternate because of the roots being too 
tough and hard to be injured, and possibly this is true of some 
forms of wireworms, but not of all, so we cannot place much 
reliance on this crop. If clover or other alternate be allowed 
to remain for one or two years after grass has been cut, veg- 



GENERAL CROP PESTS 83 

etables subject to attack can then be planted with much less 
danger of serious infestation. It is difficult with our present 
knowledge to name an absolutely immune crop. 

Poisoned baits. — An efficacious remedy is found in poisoned 
baits. One of these consists in sowing corn, soaked in water, 
containing arsenic or strychnine, over the field about ten days 
before the crop is planted and then harrowing it in. The larvae 
that attack the poisoned kernels will be destroyed. For luring 
beetles, as well as larvae, baits of sliced potatoes or other veg- 
etables, or wads of succulent vegetation, such as clover, or pig- 
weed, or sweetened corn-meal dough, are useful. These are 
poisoned in the same manner as the corn and placed about the 
fields under boards early in the season. These traps should be 
renewed as often as possible. Experiments have shown the 
futility of starvation of wireworms by clean fallowing. 

Although these remedies are not infallible against wire- 
worms, they are of value in certain sorts of soils against some 
species, and they serve in a manner to destroy white grubs and 
cutworms which are also apt to be present. 

APHIDES, PLANT-BUGS AND RELATED INSECTS 

Nearly all forms of plants are attacked by sucking insects, 
the aphides, plant-bugs, leafhoppers and numerous related 
forms. The best known are the aphides or plant-lice, many 
of which do injury to vegetable crops. Among other insects 
which obtain nourishment by suction are several species of 
true bugs of the family Capsidae, generally termed plant-bugs, 
although some forms are also known as leaf-bugs, chinch bugs, 
and other names indicative of their habits or appearance. The 
commonest and most injurious of these insects to vegetables are 
two forms of false chinch bugs, the tarnished plant-bug and 
garden flea-hopper. The thrips also obtain their food by suc- 
tion, and for convenience may be included in the same category, 
although they are not closely related to them structurally. 



84 INSECTS INJURIOUS TO VEGETABLES 

Aphides or Plant-lice. — Nearly every one knows the plant- 
lice or aphides, since there are few succulent plants that are 
exempt from their attack. Many staple crops of the field, 
garden, and orchard are very severely damaged when these 
insects multiply in unusual numbers, as so frequently happens. 
Aphides are also known as "lice," "aphis" and "green fly." 

There are many species, as varied in appearance as in habits, 
and although they have attracted attention for years on account 
of the injuries which they cause and their interesting habits, 
they are perhaps less understood than any large group of insects 
which could be named. In fact, we are not as yet able to estab- 
lish beyond a certain degree of doubt the identity of some of our 
most injurious forms and we know less of their life economy. 

Gardens are seldom free from their attacks, and cabbage and 
like crops, melons, cucumbers and similar plants, peas and young 
budding fruit trees suffer severely in some seasons. 

The best-known aphides are soft-bodied and green, very 
minute in size, with long legs and antennae. Immense masses 
of them frequently congregate on single plants, sometimes over- 
running entire fields. If a mass be closely examined it will be 
seen that many are wingless during the greater part of the 
season ; later, however, there are many which develop wings 
and are capable of flight. There are many stages of these in- 
sects, but the body is usually formed more or less like a pear, 
and the winged forms have two pairs of very delicate trans- 
parent wings with a few simple veins. The first and second 
pairs of wings are usually connected as in wasps and bees, by 
a hooklet. The haustellum or beak by which aphides obtain 
their food is three-jointed and of variable length. The eyes 
are compound and project prominently at the sides of the head. 
The aphides exude "honey-dew," a transparent fluid with 
a sweetish taste. Frequently it is excreted in such quantity 
that it forms a shining cover to the leaves of plants. The 
honey-dew of most species is very attractive to a number of 



GENERAL CROP PESTS 



85 



other insects — ants, wasps, bees and flies — and in the fond- 
ness of ants for this substance there is developed a curious 
inter-relationship. 

The various phases of development, the varieties of forms 
produced by some genera, in fact, the life economies of these 




Fig. 47-— Melon aphis, a. Winged female; 
oa, enlarged antenna of same; ab, dark 
female, side view: b, young nymph or 
larva c, last stage of nymph; d, wingless 
female — all greatly enlarged. (Author s 
illustration, U. S. Dept. Agr.) 




Fig. 48.— Flavescent leaf- 
hopper (Empoasca flaves- 
cens). Highly magnified. 
(Author's illustration, U.S. 
Dept. Agr.) 



insects would fill several volumes, and there is such great 
diversity of habit that it is difficult to generalize. 

The species which feed upon vegetable crops live for the most 
part on the under surface of leaves; but some are root- feeders, 
and the destructive grape phylloxera is an example of one of 
these subterranean forms which produce galls. 

The melon aphis (fig. 47) is one of our commonest and best 
known vegetable-feeding forms of this class. 

The best remedies for aphides are kerosene emulsion, fumiga- 
tion with bisulphid of carbon and with tobacco extracts, clean 
cultural methods of farming and the encouragement of natural 
enemies. These remedies are considered on pages 165 to 168. 

The Leafhoppers. — Leafhoppers are familiar to nearly 
everyone, although not everybody knows them by this name. 



86 INSECTS INJURIOUS TO VEGETABLES 

As we walk over lawns and through meadows and pastures 
generally, particularly in midsummer and later, myriads of 
these minute creatures fly up and are sometimes annoying by 
getting into our faces and even our eyes. Recently their true 
economic value has been ascertained, and this was brought 
about mainly through the studies of Prof. Herbert Osborn, in 
Iowa. They are most numerous in grasses from which they 
drain the vitality by sucking the sap from the blades. It has 
been estimated that between one-fourth and one-half of all the 
grass growing annually is destroyed by leafhoppers, a startling 
statement but borne out by actual observation. Although most 
of these insects feed on grasses, there are some which, partic- 
ularly in their later stages as nymphs and as adults, attack 
various vegetables and other plants. Leafhoppers are mostly 
small, some very minute and slender, with short heads more or 
less crescent-shaped, and with long hind-legs which fit them for 
jumping. They also have long wings and are strong flyers. 
The species illustrated (fig. 48) attacks a variety of vegetables. 

In their attacks on plants the usual method is to puncture the 
cells from the under side of the leaves, causing yellowish, 
brownish or other discolored spots to appear later. When 
punctures are numerous entire leaves wilt and die. A few forms 
attack culinary vegetables by preference, but most others occur 
on different plants. No less than thirty distinct species have 
been found on beets. 

Methods of Control. — Several methods have been devised 
for keeping leafhoppers in subjection. The standard remedies 
are kerosene-soap emulsion and sprays of soap. An underspray- 
ing is always necessary. The spray should be as fine as possible, 
and applied upon the first appearance of the insects, not only to 
produce the best effect, but because by using it early in the 
spring the insects may be prevented from developing in large 
numbers later in the season, for with many forms there are two 
and sometimes three generations produced annually. 



GENERAL CROP PESTS 87 

Leafhoppers may also be captured on sticky surfaces, and 
one good way of destroying them in small gardens is by causing 
them to fly up and capturing them on large frames coated with 
sticky substances such as coal tar. If this method is persisted in 
for several days few of the insects will be left, as they are 
readily caught. A good time for this work is just before sun- 
down. Special hopper-dozers are used for leafhoppers, similar 
to those described as grasshopper destroyers (page 71). Some 
of these are termed "hopperettes." 

The Tarnished Plant-bug (Lygus pratensis Linn.). — This bug 




Fig. 49 —Tarnished plant- bugr. Adult at left: last stage of nymph at right 
(Author's illustration, U. S. Dept. Agr.) 

is one of the most troublesome of its kind. It is found prac- 
tically everywhere in North America, and attacks many plants, 
cultivated and wild. It occurs throughout the warm season, and 
frequently does damage to vegetables and to trees grown in 
nurseries. The mature plant-bug (fig. 49) is of nearly elliptical 
form, and considerably flattened. The head is nearly triangular, 
with the eyes showing prominently at the sides. It is pale, 
obscure, grayish brown, marked with black and yellow, the 
thorax also with red. The length is about one-fifth of an inch. 
With little doubt this plant-bug has five stages of the nymphs 
to agree with related species which have been traced through 
their metamorphoses. The first stage measures only about one- 



SS INSECTS INJURIOUS TO VEGETABLES 

twentieth of an inch, and is yellowish green. This species is 
quite injurious to cabbage, turnip, potato and cucumber, and 
attacks also salsify and celery. The principal injury is ac- 
complished in the spring, by the adults piercing and sucking 
the juices from flowers and leaf-buds, and later by attacking 
tender fruits and shoots. 

The tarnished plant-bug is credited with being the author of 
"buttoning" of strawberries, and forms of "blight," the insect 
in the latter case acting as a transmitter of germs from dis- 
eased to healthy plants. Were it not that this plant-bug dis- 
tributed its attack by feeding on a variety of crops and weeds, 
it would be more injurious than it is. The bugs are extremely 
active, quick of flight as well as of foot, and when disturbed 
have the habit, in common with kindred species, of hiding by 
dodging to the opposite side of a plant. Hibernation is usually 
in the adult stage. In early spring, the females deposit their 
eggs singly on plants, continuing for two weeks or longer. 
According to Prof. J. M. Stedman, three generations develop 
in southern Missouri, and two in the northern portion of that 
state. The duration of the life cycle may be placed approx- 
imately at about four weeks, or a little longer, the length of 
time depending on season and climate. 

Remedies. — The standard bug remedy, kerosene emulsion, is 
the best, sprayed on as thoroughly as possible to all crop plants 
as well as weeds attacked. Pyrethrum is of value, but must be 
applied repeatedly and is rather expensive. Hand methods are 
also valuable, and a hand net is useful for sweeping the plants 
and surrounding grass and other vegetation. Frequently more 
individuals can be captured in this way than in any other. 
When a considerable number have been taken, they can be killed 
by throwing them into large pans of water with a few drops 
of kerosene. After the crop is off "back firing" should be 
practiced in the same manner as described as a remedy for 
army worms on page 58. 



GENERAL CROP PESTS SO, 

The Onion Thrips (Thrips tabaci Lind.). — Few gardeners 
are unacquainted with "thrips," of which there are several 
species injurious to plants grown under glass. The commonest 
and most destructive vegetable-feeding species in America are 
the onion thrips and the wheat thrips. 

All thrips are exceedingly minute, the common species not 
exceeding one-twentieth of an inch in length. They have 




Fig. 50.— Onion thrips. a, Adult; b, antenna of same; c, young larva; d, full-grown 
larva— greatly enlarged. (Howard, U. S. Dept. Agr.) 



elongate bodies, and the winged lorms have four very slender 
wings fringed with long, delicate hairs. These insects are 
somewhat anomalous in the manner of their feeding: their 
mouth-parts are fitted chiefly for sucking, but they also have 
bristle-like mandibles. 

The general appearance of the onion thrips is shown in 
figure 50, a, highly magnified. It is pale yellow, with the thorax 
somewhat darker. The wings are paler yellow, with dusky 
fringes and bristles. 

The parent insects are usually found on the lower sides of 
leaves or imbedded in flowers of various kinds. In their attacks 
they induce the withering of the parts affected, and they some- 
times destroy entire plantings. The onion thrips injures a great 
variety of field and garden crops, to which it is quite as de- 
structive as to plants grown artificially. Besides onion it in- 
juriously affects garden leek, parsley, cabbage, celery, melon, 



90 INSECTS INJURIOUS TO VEGETABLES 

cucumber, squash, turnip, cauliflower and strawberry, and does 
more or less damage to nasturtium, mignonette, carnations, 
candytuft, four-o'clock and rudbeckia. 

The female thrips cuts a slit, in a leaf or stem usually, to 
deposit her eggs. In a few days the young thrips work their 
way out and begin to feed. They suck the juices of plants and, 
as they feed continuously, their growth is rapid. The entire 
life cycle from the time of the deposition of the eggs until the 
maturing of the adult is passed under favorable conditions, in 
a warm atmosphere, in three weeks. Out-of-doors in a cooler 
atmosphere a longer period would be required for the life cycle. 

The minute size of thrips, with their habits of feeding by 
suction, in concealment in their host plants, renders it difficult 
to treat them successfully. The best contact poisons are dilute 
kerosene-soap emulsion, applied as for aphides (p. 361). It 
is practicable in some cases to dip whole plants, when being 
transferred from the hothouse to the field, in kerosene 
emulsion. 

For fumigation, hydrocyanic-acid gas, carbon bisulphid and 
different preparations of tobacco are useful. Tobacco prepara- 
tions, containing about 40 per cent, nicotine, have been found 
effective at the rate of 5 or 6 teaspoonfuls to 1^ pints of water 
when vaporized in a space of 5,000 cubic feet. This method does 
not injure cucumbers while nearly all the thrips on plants thus 
treated are killed. 

In the field drenching affected plants with a hose will kill 
many of the pests. Clean methods of farming is a necessity, 
as thrips develop largely in grasses, weeds and other vege- 
tation in and near onion fields. All other infested plants should 
also be treated with kerosene-soap emulsion, and the weeds 
burned where possible. 

The Wheat Thrips (Thrips tritici Fitch). — This native spe- 
cies, also called the strawberry midget, has been reported as 



GENERAL CROP PESTS 



91 



doing injury to parsley, pea, endive, cotton, orchard and small 
fruits and roses. Its color is yellow, with the thorax tinged 
with orange, and the antennae or feelers are ringed with a dusky 
color- (fig. 15). It is distributed from Canada to Florida, and 
westward. 

Remedies. — The same as for the onion thrips. 

The Red Spider (Tetranychus bimaculatus Haw.). — Few 
vegetables are free from the attacks of red spider (fig. 50^). 
These creatures are extremely 
minute, and are frequently 
not noticed until they become 
excessively numerous, as hap- 
pens during summer droughts. 
They do considerable damage 
in vegetable gardens and to 
plants grown under glass. 

Remedies. — Flowers of sul- 
phur, mixed with water at the 
ration of one ounce to the 
gallon, and sprayed over the 
plants, is of great value in 
eradicating this pest. Fish-oil 
and other soap solutions are Fi s- 50x.-Red spider, a, Adult; b. palpus; 

c, claws. (After Banks, U. S. Dept. Agr.) 

valuable, and the addition of 

sulphur increases their effectiveness, but are too strong for 
some delicate plants. Greenhouse plants are sprayed with 
water two or three times a week during the growing season, 
and care is exercised to wash off the spiders and not drench 
the beds. 





Fig. 51 



-Spray of asparagus, with common asparagus beetle in different stages 
Natural size. (Author's illustration, U. S. Dept. Agr.) 



92 



CHAPTER VI 



INSECTS INJURIOUS TO ASPARAGUS 

Asparagus was introduced into America with the early settlers 
from Europe, and was cultivated here for two hundred years 
before being troubled with insects. Few edible plants down to 
the time of the Civil War have enjoyed such immunity from the 
ravages of insects. The principal insect enemies of asparagus 
are two leaf-beetles, both imported from the Old World, and 
limited for food supply to this plant. 

The Common Asparagus Beetle (Crioceris asparagi Linn.), 
as its English name indicates, is the more abundant asparagus 




Fig. 52.— Common asparagus beetle, a, Beetle; b, egg; c, newly-hatched larva; d, 
full-grown larva; e, pupa— all enlarged. (Author's illustration) 

beetle and by far the most important foe of this plant. Its first 
appearance was noted in this country at Astoria, near New 
York City, in i860, where it was introduced about 1856. 

The injury inflicted by this insect is due to the work of both 
adults and larvae upon the tender shoots, which they render 
unfit for market early in the season. Later they destroy by 
defoliation growing plants, and are particularly injurious to 

93 



94 INSECTS INJURIOUS TO VEGETABLES 

seedlings, the roots of which are weakened by having their tops 
devoured. Larvae, as well as beetles, attack the tenderest por- 
tions of the plants, but the latter gnaw with seemingly equal 
relish the epidermis, or rind, of the stems. 

The beetle, illustrated by figure 52, is a most beautiful creature, 
slender and graceful in form, blue-black in color, with red 
thorax, and lemon-yellow and dark-blue elytra or wing-covers, 
with reddish border. Its length is a trifle less than one-fourth 
of an inch. 

From the scene of its first colonization, Queens County, N. Y., 
the insect migrated to other truck-growing regions, and has 
now extended its range northward through Connecticut and 
Massachusetts to the State line of New Hampshire. Southward 
it has traveled to southern Virginia. At the present time it is 
well established in the principal asparagus-growing sections of 
the northern Atlantic region, and occurs westward to Illinois 
and Michigan. In a very few years we may expect its spread 
to other portions of states in which it is now local, and later 
it will naturally move westward. 

The insect passes the winter in the beetle state under con- 
venient shelter, and in April or May, according to locality, or 
at the season for cutting asparagus, issues from its hibernating 
quarters and lays its eggs for the first brood. The eggs are 
deposited endwise upon the stem or foliage and in early spring 
on the developing stalks, in rows of from two to six or more. 

In from three to eight days the eggs hatch, the young larvae, 
"grubs" or "worms," presenting the appearance indicated in 
figure 52, c. They at once begin to feed, and are from ten days 
to a fortnight in attaining full growth. When full grown the 
larva appears as in figure 52, d. It is soft and fleshy, and in 
color is dark-gray or olive, which becomes lighter and yellowish 
with age. The mature larva enters the earth, and here, within 
a little rounded, dirt-covered cocoon which it forms, the pupa 
state is assumed. In from five to eight or more days the beetle 



INSECTS INJURIOUS TO ASPARAGUS 95 

is produced, which issues from the ground in search of food 
and of a suitable place for the continuance of the species. The 
duration of the life cycle, according to Fitch, is about thirty 
days from the time the egg is laid until the insect attains matur- 
ity. In the District of Columbia the eggs, in the warmest part 
of midsummer, develop in three and the pupae in five days. In 
the present range of the species two and perhaps three broods 
are usually produced. The beetles enter into hibernation in 
September. 

The asparagus beetle has efficient checks in predaceous in- 
sects, which prey upon its larvae and assist in preventing its 
undue increase. Among these are the spotted ladybird (Megilla 
maculata DeG.), the spined 
soldier-bug (Podisus maculi- 
vintris Say) and the bordered 
soldier-bug (Stiretrus anchor- 
ago Fab, fig. 53). Wasps 
and small dragon flies also 
prey upon the larvae. Im- 
mense numbers of beetles are 

«■ 

sometimes killed in winter dur- 

, 1t ... Fig. 53.— Bordered soldier-bug. Enlarged 

ing Severe cold spells follow- (Author's illustration, U.S. Dept.Agr.) 

ing "open" weather. 

Remedies. — The common asparagus beetle, under ordinary 
circumstances, may be held in restraint by the simplest means. 

Chickens and ducks are efficient destroyers of them, and their 
services are often brought into requisition for this purpose. 

A practice in high favor is to cut down all plants, including 
volunteer growth, in early spring to force the beetles to deposit 
their eggs upon new shoots, which are then cut every few days 
before the eggs hatch. Another measure of value consists in 
permitting a portion of the shoots to grow and serve as lures 
for the beetles. Here they are killed with insecticides, or the 
plants after they become covered with eggs are cut down and 
burned, and other shoots are allowed to grow up as decoys. 




96 INSECTS INJURIOUS TO VEGETABLES 

One of the best remedies against the larvae is fresh, air-slaked 
lime dusted on the plants in the early morning while the dew 
is on. It quickly destroys all the grubs with which it comes 
in contact. 

The arsenicals, applied dry in powder mixed with lime, an- 
swer well, and possess the advantage of destroying beetles as 
well as grubs, and are of value upon plants that are not being 
cut for food. To produce satisfactory results the lime or arsenite 
must be applied at frequent intervals, or as often as the larvae 
reappear on the beds. Arsenate of lead is an excellent remedy. 

A simple method of killing the larvae in hot weather is to 
brush them from the plants so that they will drop to the heated 
earth, where they die before being able to return. 

The Twelve-spotted Asparagus Beetle (Crioceris 12-punctata 
Linn.). — The chief source of damage from this species is from 
the work of the hibernated beetles in early spring on young and 
edible asparagus shoots. Later the beetles as well as larvae ap- 
pear to feed exclusively on the berries. The eggs are deposited 
singly, and apparently by preference, on old plants toward the 
ends of shoots, which, lower down, bear ripening berries, and 
they are attached along their sides instead of at one end, as 
with the common species. Soon after the larva hatches from 
the Qgg it finds its way to an asparagus berry, enters it, and 
feeds upon the pulp. In due time it leaves this berry for an- 
other one, and when full growth is attained it deserts its last 
habitation and enters the earth, where it transforms to pupa 
and afterwards to the beetle. The life cycle does not differ 
materially from that of the common species, and there are 
probably as many generations developed. 

This species is at present distributed throughout nearly the~ 
same territory of the North as the preceding. The beetle rivals 
the common asparagus species in beauty, but may be distin- 
guished by its much broader wing-covers and color. It is orange 
red, and each wing-cover is marked with six black dots, and the 
knees and a portion of the under surface of the thorax are also 



INSECTS INJURIOUS TO ASPARAGUS 



97 



marked with black (fig. 54, a). The beetle as it occurs on plants 
when in fruit very closely resembles, at a little distance, a ripe 
asparagus berry. 
The full-grown larva is shown at figure 54, b. It measures, 




Fig 54 —Twelve-spotted asparagus beetle, a. Beetle; b, larva: c, second abdominal 
segment of larva; d same of common asparagus beetle, a, b, Enlarged; c, d, more 
enlarged. (Chittenden. U S Dept. Agr.) 



when extended, three-tenths of an inch, being of about the same 
proportions as the larva of the common species, but is readily 
separable by its ochraceous orange color. 

Remedies are those indicated for the common asparagus 
beetle, with the exception of caustic lime and other measures 
that are directed solely against that species, but the habit of 
the larva of living within the berry places it for that period 
beyond the reach of insecticides. 

The Asparagus Miner (Agromysa simplex Loew.). — Aspara- 
gus stalks are sometimes considerably injured by a maggot 
(fig. 55#, a) which mines under the skin near or just beneath 
the base. The appearance of the affected stalk (/) is charac- 
teristic. The parent insect is a small black fly. 

Remedial Suggestions. — Permit a few volunteer asparagus 



9 8 



INSECTS INJURIOUS TO VEGETABLES 



plants to grow as traps to lure the female fly to deposit her 
eggs Afterward, in late June or early July, pull the trap 




Fig. 55 —Criocevis 12- 
punctata. Egg, natur- 
al size, on asparagus, 
right; enlarged at left. 
(Chittenden, U. S. 
Dept. Agr.) 




Fig. 5 5x-— Asparagus miner, a, Larva; b, c, 
spiracles; d, e, puparium, /. section of asparagus 
stalk, showing injury and puparia. a-e, Much 
enlarged; /, slightly reduced. (Author's illus- 
tration, U. S. Dept. Agr.) 



plants and promptly burn them with their contained insects (in 
the flaxseed stage, fig. 55^, d, e). 

If this is carefully done over a considerable area, there 
will be little necessity for other methods, as few insects will 
be left for another season; unless, indeed, this insect has an 
alternate food plant. Cooperation and thoroughness are essen- 
tials for success. This method will operate also against the 
rust which is ofteji present in fields infested by the miner. 



CHAPTER VII 



. INSECTS INJURIOUS TO BEANS AND PEAS 

Edible legumes are subject to injury by certain weevils, 
which deposit their eggs upon or within the pods on the grow- 
ing plants and develop within the seed. The specific enemy of 
the pea is the pea weevil, and of the bean, the common bean 
weevil, both of sufficiently wide distribution and abundance to 
hold high rank among injurious insects. The inroads of these 
weevils in seeds cause great waste, and particularly is this true 
of seed kept in store for any considerable tmie. In former 
times popular opinion held that the germination of leguminous 
food seed was not impaired by the action of the larval beetle in 
its interior, but this belief is erroneous, as will be shown in the 
discussion of the nature of the damage by the pea weevil. 

Although it is not probable that any serious trouble follows 
the consumption by human beings of the immature weevils in 
green peas or beans, the use for food of badly infested dry 
seed filled with' the dead bodies and excrement of the beetles 
would naturally be attended with Unpleasant consequences. 

Growing pods in the fields are invaded by the bollworm and 
pea moth, and the foliage is preyed upon by numerous insects. 
Of foliage feeders are the bean leaf-beetle, bean ladybird, 
blister beetles, cutworms, and other caterpillars. Several forms 
of plant-bugs, leafhoppers, and aphides also exhaust the plants 
by sapping their juices. 

The Pea Weevil (Bruchus pisorum Linn.). — Seed peas are 
often found with a single round hole in them, due to the attack 
of the pea weevil or "pea bug," the largest of the pea and bean- 

99 



IOO INSECTS INJURIOUS TO VEGETABLES 

feeding weevils found in this country, measuring about a fifth 
of an inch in length. Its ground color is black, but it is thickly 
covered with brown pubescence, variegated with black and 
white markings arranged as illustrated in figure 57, a. 

©In 1748 the celebrated Swedish naturalist Pehr 
Kalm gave an account of this weevil, stating 
that the culture of the pea had been abandoned in 
Fig. 5 6. -A Pennsylvania, New Jersey, and southern New 
buggy pea York on account of it. 

There are reasons for believing that this species came orig- 
inally, with so many other injurious insects which live upon 
cultivated seeds, from the Orient, and it has now become dis- 
tributed over nearly the entire globe, wherever peas are culti- 
vated. It does comparatively little damage in the colder parts 
of Canada; hence, seed peas for planting in the United States 
are largely imported from Canada or are bought from seed 
dealers who obtain them from our more northern states. 




Fig. 57.— Pea weevil, a, Adult beetle; b, larva; c, pupa. All greatly enlarged 
(Author's illustration, U. S. Dept. Agr.) 



Nature of injury. — Every pea in a pod is sometimes infested 
with this weevil ; and although nearly every one is familiar with 
"buggy" peas, it is not generally known that in eating green 
peas we often eat also a "worm" with nearly every pea. The 
only external evidence of infestation in a green pea is a minute 



INSECTS INJURIOUS TO BEANS AND PEAS IOI 

dot on its surface, but in dry seed the cell inhabited by the 
insect is visible under the skin. 

The belief was once more or less prevalent that the larva 
working within the seed, by some wonderful instinct, avoided 
the germ or embryo, and that weevil-infested peas were there- 
fore of equal value for seed to uninfested ones, but this is in- 
correct. Many "weeviled" seed will germinate, but as they are 
deficient in plant food the resulting plant is apt to be weakly 
and nonproductive. 

This species develops only a single generation annually. As 
it does not breed in dry peas, the new generation for another 
year is dependent on such beetles as are contained in planted 
seed or which escape from the storeroom. 



REMEDIES 

Holding over seed. — A simple and effective remedy consists 
merely in keeping seed peas in a close receptacle, a tight bag 
or box, over one season before planting. The beetles which 
issue die without being able to lay their eggs in the field. 
Primary injury to the seed has been effected by the larva the 
first summer and after the weevil develops, always during the 
first autumn in the writer's experience, further damage prac- 
tically ceases. 

Late planting. — Comparative immunity from pea weevil at- 
tack is claimed in some localities, e. g., in the southern states, 
by planting late, and is all that is necessary to secure sound 
seed stock. 

Bisulphid of carbon. — When it is desired to plant the first 
season after gathering the seed, bags in which peas have been 
kept tightly closed should be placed in a tight box or vessel and 
disinfected with bisulphid of carbon, at the rate of an ounce 
or two to ioo pounds of seed. This method will kill the weevils 



102 



INSECTS INJURIOUS TO VEGETABLES 




Fig. 58.— Common bean weevil. 
Greatly enlarged. (Author's 
illustration, U. S. Dept. Agr.) 



without injury to the germinative property of the seed. A 
similar remedy consists in soaking infested seed for one minute 
in boiling water. A longer time is apt to injure it for planting. 

No efficient preventive of in- 
jury is known, but cooperation 
in the treatment of infested seed 
would render further action un- 
necessary. 

The Common Bean Weevil 
(Bruchus obtectus Say). — The 
most formidable enemy to the 
culture of beans is the common 
bean weevil. In the nature of 
its attack it differs from the 
pea weevil in that it not only 
develops in the pods in the field 
but continues to breed for suc- 
cessive generations in seed, after harvest and storage, until the 
seed is useless for planting or as food for man or stock. 

As with peas, the market gardens of the North provide the 
dry seed for consumption and for planting in the Southern 
States. In and about Washington, D. C, it is next to impos- 
sible to procure a crop of beans uninfested by this weevil; 
hence, the stores of the city are supplied mainly from the North, 
New York State furnishing the greatest quantities. 

This bean weevil is smaller than the preceding, averaging 
about an eighth of an inch in length. It is coated with fine 
brown-gray and olive pubescence which gives the body that col- 
or. The wing-covers are mottled, as shown in figures 58 and 60. 
From the pea weevil this species may be known by the different 
shaped thorax and the two small teeth in addition to the large 
tooth with which the thighs are armed. In figure 60, a, the beetle 
is represented in profile with its head bent under in natural 



INSECTS INJURIOUS TO BEANS AND PEAS 



103 



resting position. Until recently this species, like the preceding, 
was generally believed to be indigenous. It is certainly not 
native to the United States, and if introduced from the Eastern 
Hemisphere probably became acclimated in tropical America 
before establishing itself in the North. Its distribution is now 




Fig. 59.— Bean 

showing in jury- 
by common bean 
weevil. (From 
Riley.) 




Fig. 60.— Bean weevil, a, In profile; b, section of 
bean-pod showing slit for egg deposit; c, portion of 
interior of pod showing egg mass inserted through 
slit, a, c, Much enlarged. (Reengraved from 
Riley, U. S. Dept. Agr.) 



world-wide. It occurs in nearly every State and Territory of 
the Union, and is generally diffused through Central and South 
America. 

Oviposition takes place primarily in the field, the eggs being 
deposited, as with the pea weevil, upon or inserted in the 
pod through a hole made by the female and through openings, 
such as are caused by its drying and splitting. In shelled beans 
the eggs are dropped loosely in the receptacle in which they 
are stored, or are placed in holes made by the weevils in their 
exit from the seed. Less seldom they are attached to the outer 
surface of the seed. 

There are probably produced annually an average of six 
generations in latitudes such as the District of Columbia and 
a less number in more northern localities. Unlike the pea 
weevil, a large number of individuals will develop in a bean, 
as many as twenty-eight having been found in a single seed. 



104 INSECTS INJURIOUS TO VEGETABLES 

Any single indoor generation is capable of exhausting seed and 
completely ruining it for food or planting or any other practical 
purpose. The beetles begin to issue in the field in a climate like 
that of the District of Columbia as early as October, when in 
the natural course of events the eggs for a new brood would 
be deposited in such pods as had cracked open so as to expose 
the seeds within. This beetle prefers the bean as a host plant, 
but it will also breed in cowpeas in the field as well as in store, 
and in confinement develops in dried peas, lentils, and chick- 
peas. It is no more true of seed infested by this species than 
of that attacked by the pea weevil that germination is not im- 
paired by the work of the weevil in the bean. Weeviled beans 
should not be planted. In a test only 50 per cent, of the infested 
seed used germinated, and only 30 per cent, could have passed 
the germinating stage, and these, owing to injury to the seed 
leaves, would probably have produced plants of low vigor and 
correspondingly low productiveness. 

Remedies. — From the fact that this species breeds continuously 
in dried seed, neither the expedient of holding over seed for 
a year before planting nor that of planting late for seed stock 
would be productive of good, as in the case of the pea weevil. 
Recourse must therefore be had to fumigation or to heat, and 
the earlier the seed is treated after it has been gathered the 
better the result. Just before it is planted seed infested with 
this bean weevil should be lightly thrown into water. Badly 
injured seed will float, and may be picked out or poured 
off and destroyed. Sound seed only should be reserved for 
planting. 

The Cowpea Weevil (Bruchus chinensis Linn.). — Cowpeas 
are quite liable to be infested by the cowpea weevil and the 
four-spotted bean weevil, which injure its seed in the same 
manner as the common bean weevil. Like that species they 
begin work in the field and continue to breed in the stored seed, 




INSECTS INJURIOUS TO BEANS AND PEAS 10$ 

until they entirely spoil it, or seriously impair its germinating 
power. Both species are generally distributed and injurious 
in the South, and are widening their range with the increasing 
use of their food plant as a soil renovator and as forage. They 
resemble each other after a manner superficially, in appearance 
as in habit, but they differ to some ex- 
tent in various details of their life econ- 
omy as well as in structure. 

The cowpea weevil may be readily dis- 
tinguished from the kindred four-spotted 
species by the two large, elevated ivory- 
like lobes at the base of the thorax and 
by the strongly pectinate antennae of the 
male (fig. 61). This is undoubtedly an 

Old World species and an ancient enemy Fi f; *i --Cowpea weevil 
r J (Author's illustration. 

of edible pulse. u. s. Dept. Agr.) 

Cowpea is the favorite food seed, but 
the insect is also injurious to common and pigeon peas, lentils, 
chick-pea and "mungo." Table beans also serve as food. Mate- 
rial infested by this weevil undergoes a marked elevation in 
temperature. In one instance the temperature of a small sack 
of seed infested by the cowpea weevil was found to be 25 F. 
higher than the surrounding atmosphere. 

Remedies. — The similarity of the habits of this and the com- 
mon bean weevil renders it amenable to the same remedies. 

The Four-spotted Bean Weevil (Bruchus quadrimaculatus 
Fab.) is the more slender species and differs from the cowpea 
weevil by many characters. What appears to be the commonest 
form of coloration is illustrated in figure 62, a, which is suffi- 
cient to separate it from the preceding which it much resembles, 
especially in its manner of life. 

The Remedies are practically the same as for the common 
bean weevil. 



I06 INSECTS INJURIOUS TO VEGETABLES 

The Seed-corn Maggot (Pcgomya fusciceps Zett). — When 
the seeds of beans, peas, corn and other plants fail to 
develop, damage is frequently due to a maggot which works 
by scraping the seeds, sprouts, roots, stalks, and stems of 
plants underground. 1 Where this insect works decay soon sets 
in and the plants die. Entire plantings are sometimes destroyed, 
but when only a few seeds or sprouting plants are attacked, 




Fig. 62.— Four-spotted bean weevil, a, Beetle; b, larva; c, pupa 
All enlarged. (Author's illustration, US. Dept. Agr.) 

injury may escape notice. Early crops suffer most and if they 
can be preserved until larger growth they will as a rule sustain 
considerable attack without material damage. 

The insect in question is called the seed-corn maggot and 
bean fly, and its parent looks like a small house fly. It can be 
identified by the male (fig. 63, a). 2 The female can scarcely be 
distinguished from related species, such as the adults of the 
cabbage root-maggot and onion maggot. The length is about 
one-fifth inch and the wing expanse about two-fifths. The larva 
is footless and of cylindrical form (d), narrowed at the anterior 
extremity and, enlarged posteriorly. It is considerably smaller 

1 Injury of this character is also committed by wireworms, white grubs and 
some other insects, e. g., weevils in the seeds. 

2 His principal characteristics consist of a row of short, rigid, bristly hairs 
of nearly equal length on the inner side of the posterior tibiae or shanks. 



INSECTS INJURIOUS TO BEANS AND PEAS 



107 



than the ©nion maggot, measuring about one-fourth of an 
inch. 

This fly is evidently of European origin, and was first rec- 
ognized in New York State in 1856. Like so many other flies, 
it ranges through several life areas, and we know of its occur- 
rence in New England, Canada and Minnesota, southward to 
the Gulf, and westward to the Pacific. 

Injury is most severe to young plants, and particularly to 
beans, peas, and Indian corn. Cabbage, turnip, radish, beets, 
9> 4 




Fig-. 63.— Seed-corn maggot, a, Male fly," c, head of female; d, larva, from side; 
e, anal segment of larva; /, anal spiracles; g, thoracic spiracles; h, puparium. 
All much enlarged. (Author's illustration, U. S. Dept. Agr.) 

onion, seed potato and hedge mustard are also attacked, and the 
maggots even feed on the eggs of grasshoppers. The insect 
apparently breeds on decaying vegetable and perhaps animal 
matter of various kinds. A single generation only develops in 
corn, but later ones might be produced on bean and pea, owing 
to the longer period in which these crops are grown. The flies 
are found southward throughout the year, but in the north there 
must be a period in midwinter in which breeding ceases; per- 
haps also another in midsummer. 



I08 INSECTS INJURIOUS TO VEGETABLES 

METHODS OF CONTROL 

Owing to the difficulty of destroying root-maggots and the 
cost of the chemicals, growers depend largely upon methods of 
prevention which should be employed before the insect's eggs 
are laid. 

Sand and kerosene, for deterring the parent flies from de- 
positing their eggs, consists in placing sand soaked in kerosene 
— a cupful to a bucket of dry sand — at the base of the plants, 
along the rows. This will also kill young maggots that might 
attempt to work through it. 

Mineral fertilisers are useful as deterrents, if employed just 
before or after a shower has thoroughly wet the ground. The 
principal fertilizers for the purpose are kainit, nitrate of soda, 
and chlorid of potash. They are used as top dressings before 
planting; and afterwards, when they should be applied as nearly 
as possible to the roots, the earth being turned away from the 
plants for this purpose. These fertilizers possess the advantage 
of acting also as a stimulant to plant growth, thereby facilitating 
recuperation from root-maggot attack. 

Danger from organic fertilisers. — Stable manure and organic 
fertilizers are apt to induce infestation, since this species devel- 
ops in excrement and other decomposing material. Numerous 
instances of this have come to the writer's knowledge. It is 
advisable, therefore, to avoid the use of manure, rotted leaves, 
or other organic fertilizers, and to avoid planting in fields in 
which there have been infested or diseased plants. 

Hellebore is used with some degree of success in Canada as 
a remedy for the cabbage and onion maggots. 

Carbolic acid emulsion diluted about 35 to 50 times, is partic- 
ularly applicable when this species occurs in radish and other 
plants than cabbage and cauliflower. 

Hand-picking, although laborious, has the merit of effective- 
ness and has been practiced with much success by extensive 
growers. It consists in lifting out the young plants, examining 



INSECTS INJURIOUS TO BEANS AND PEAS IO9 

the roots for the maggots, and washing them in a strong solu- 
tion of soap, after which they are replanted and in two or three 
weeks show no ill effects of the treatment. By careful watching 
the eggs may be seen about the stalks of the young cabbage 
plants, and if the soil about these plants be raked away so as 
to expose the eggs to the sun they will dry up, thus preventing 
the maggots from hatching. 

Covering young plants of cabbage and cauliflower in seed- 
beds is also practiced with some success in Canada. 

The Bean Ladybird (Epilachna corrupta Muls.). — This species 
is limited in its operation as regards the number of crop plants 




ah o d 

Fig. 64.— Bean ladybird, a, Larva; b, beetle; c, pupa; d, egg mass. All about three 
times natural size. (Author's illustration, U. S. Dept. Agr.) 

affected and the territory invaded. It is one of three native 
ladybirds that live by choice on vegetables, the ®thers being 
predaceous and subsisting largely on plant-lice and soft-bodied 
larvae. It is nearly hemispherical, and its length is a little more 
than a fourth of an inch. In color it is light yellowish brown, 
and each wing-cover bears four black spots (fig. 64, b). 

Its distribution comprises Colorado, New Mexico, Arizona, 
western Kansas, and Mexico. 

The insect is described as being the worst enemy to the bean 
crop in the West, its work being compared to that of the Col- 
orado potato beetle. It devours all parts of a bean plant, leaves, 
flowers, and green pods. The female deposits her yellowish- 
brown eggs in large clusters (fig. 64, d), and the larvae feed 
chiefly on the lower sides of the leaves. The full-grown larva 



no 



INSECTS INJURIOUS TO VEGETABLES 



(a) is yellow and covered with stout branched spines. Winter 
is passed in the adult stage, and a single generation has been 
observed. 

Remedies. — Arsenate of lead is preferable to Paris green for 
use on beans since, unless great care be taken in the application 
of the latter, it is liable to scorch the leaves. Kerosene emul- 
sion has given good results, and is not open to the objection 




Fig. 65.— Bean leaf-beetle, a, Adult beetle; b, pupa; c, larva; d, side view of anal 
segment of larva; e. leg of same; /, egg', a, b, c, Enlarged about six times; d, e, f, 
more enlarged. (Author's illustration, U. S. Dept. Agr.) 

of poisoning the plants as in the case of an arsenical. Hand- 
picking the beetles and eggs on their earliest appearance is a 
measure of prevention that would compensate for the time and 
labor in kitchen gardens. 

The Bean Leaf -beetle (Cerotoma trifurcata Forst). — An in- 
sect of considerable importance in the Gulf States, and in some 
years farther north is the bean leaf-beetle. It has attracted at- 
tention by its injuries in New Jersey, Louisiana, Indiana, Dela- 
ware, Ohio, Maryland, and Virginia. Injury is due to the 
adult beetle, which eats large, round holes in growing leaves of 
bean and cowpea, and certain other leguminous plants, including 



INSECTS INJURIOUS TO BEANS AND PEAS 



III 



cultivated beggarweed or tickseed. The larvae feed on the roots 
and main stems of the same plants just below the surface. 

The beetle resembles in several particulars the cucumber 
beetles. It measures from a seventh to a fifth of an inch in 
length, and varies in color from pale yellowish or buff to dull 
greasy red, with black markings, arranged, in what appears to 
be the typical form, as in figure 65, a. Individuals occur, how- 
ever, in which the elytral marking is entirely wanting. 

This species is native and found from Canada southward to 
the Gulf States and westward to Kansas and Minnesota. 

In the South the beetles appear in April, and northward as 
late as June. The minute orange-colored eggs (fig. 65, /) are 
laid about the stem of the insects' food plant, in clusters of six 
or more, and the larvae eat 
around the stem and roots. 

Remedies. — Hand-picking and 
pyrethrum are useful in small 
gardens early in the season; but 
our chief reliance is in arseni- 
cals when the insect is numer- 
ous. Arsenate of lead should 
be employed on the first appear- 
ance of the beetles in order to 
stop them at the outset. An 
important measure is the care- 
ful weeding out of wild food 
plants, such as tick trefoil and bush-clover, in the neighborhood 
of cultivated fields. 

The Pea Moth (Semasia nigricana Steph.). — In Canada, where 
pea-growing is an important industry, there is, in addition to 
the pea weevil discussed in previous pages, a seed-infesting in- 
sect known as the pea moth, the larva of which develops in 
ripening peas in the pods. The moth (fig. 66) is a small 
Tortricid, with a wing expanse of about half an inch. The 




Fig. 66.— Pea moth (Steph) Moth above, 
larva below. About three times natural 
size. (Author's illustration, U. S. Dept. 
Agr.) 



112 



INSECTS INJURIOUS TO VEGETABLES 



larva is whitish-yellow with a pale brown head and thoracic 
shield, the latter inconspicuous. This is a comparatively new 
importation from the Old World and it is as yet unknown in the 
United States, but it will probably in- time invade our Northern 
States, and pea-growers should be warned against it. The 
remedy which gives best results is early planting of the earliest 
ripening varieties. 

The Bean Leaf -roller (Eudamus proteus Linn.). — This species 
is injurious in the Gulf States to beans, cowpea and cultivated 




Fig. 67.— Bean leaf-roller, a, Butterfly; b, larva, dorsal view; c, larva, lateral view; d, 
pupa in rolled-up leaf. Somewhat enlarged. (Author's illustration, U.S. Dept. Agr.) 



"beggarweed." It is the caterpillar of a butterfly called the 
swallow-tailed skipper. The ground color of the caterpillar is 
yellowish, its head being darker and marked with two orange 
spots near the mandibles. The head is prominent and separated 
from the body by the narrow neck, a character which will dis- 
tinguish it from any other common caterpillar on garden crops 
(fig. 67). 



INSECTS INJURIOUS TO BEANS AND PEAS 



113 



Cutworms and Other Caterpillars. — Numerous other caterpil- 
lars devour the foliage of beans and peas of which cutworms 
are among the most important, often causing extensive damage 
to young plants by cutting them off near the ground, and to 
older plants by severing their leaves and tender shoots. Cut- 
worm remedies are considered on page 54. 

A green-striped caterpillar (fig. 68), misnamed the bean cut- 
worm (Ogdoconta cinereola Guen.), does injury to the foliage 




Fig. 68.— Bean cutworm Ogdoconta cinereola). a, Moth, b. larva; c, abdominal seg- 
ments of larva; d, pupa. All enlarged. (Author's illustration, U. S. Dept. Agr.) 

and pods of beans, sometimes stripping the vines bare. Other 
troublesome species include the zebra caterpillars, the yellow 
bear and salt-marsh caterpillars. 

The boll worm or corn-ear worm (Heliothis obsoleta Fab.) is 
a very serious enemy of beans frequently destroying the seed by 
crawling into the green pods. No means of preventing this 
form of injury is known. A more extended account of this 
pest will be given under "Insects Injurious to Sweet Corn." 

The caterpillar of a beautiful little butterfly, the gray hair- 
streak (Thecla melinus Hbn.) is sometimes injurious to beans 
and peas by eating into the pods. The butterfly is on the wing 
almost continuously from May to September in the North, and 
from March to November farther South. This species seldom 



H4 



INSECTS INJURIOUS TO VEGETABLES 



does severe damage, hence little precaution need be observed in 
the treatment of it, further than to destroy all affected pods, 

4flk 




Fig. 69.— Gray hair-streak, a, b. Butterfly; c, larva; d, pupa; e, egg, much en- 
larged; others somewhat enlarged- (Howard & Chittenden, U. S. Dept. Agr.) 

that the insect may not develop and do injury later and in after 
years (fig. 69). 

It may be successfully controlled by a spraying with an ar- 
senical on its first appearance. 

The Pea Aphis (Nectarophora destructor Johns.). — Until the 
year 1899 P eas grown in the United States suffered little injury 
from insects other than the pea weevil. In that and the fol- 
lowing year, however, this crop was badly injured by the pea 
aphis, which caused enormous losses in our principal pea- 
growing regions, especially where peas are grown for canning. 
It was, in fact, one of the most destructive of all insects that 
ravaged crops in the United States at that time. 

This aphis is of unusual size among those found in gardens, 
and the largest green species which attack the pea and related 
plants. The length of the body of winged viviparous females 
is about 3/16 inch, and the total wing expanse about 4/10 inch. 
The general color of both the winged and apterous or wingless 
forms is uniform pea-green, the same as its food plants. As 
to whether this insect is native or of foreign origin there is 
still some doubt. 



INSECTS INJURIOUS TO BEANS AND PEAS II5 

During the years mentioned this pea aphis overran and laid 
waste fields, of peas from Nova Scotia to Virginia and Mary- 
land, in the last as well as neighboring States, destroying about 
50 per cent, of the annual output, and this in spite of vigorous 
efforts that were made to control it. An estimate of the loss 
for 1899 along the Atlantic Coast States reached the sum of 




Fig. 70.— Pea aphis, a, Winged female; b, same from side with wings folded in natural 
position when feeding; c, apterous female; d, nymph in last stage; e, third joint of 
antenna of winged form, a-d, Much enlarged, e, more highly magnified. (Author's 
illustration, U.S. Dept. Agr.) 

$3,000,000. During 1900 the loss over the same area was placed 
as early as June 15 at $4,000,000. Several cases of severe 
damage were reported, in which 80 or more per cent, of the peas 
on farms of 500 or 600 acres were completely destroyed. In 
short, pea-growers as far westward as Wisconsin sustained such 
severe losses as to give rise to the expression that the country 
had been visited by a veritable scourge. 

Attack begins on the young vines ; the "lice" gather in clusters 
about the terminals, and as the leaves become covered they 
attack the stems, and by their numbers and voracity sap the 
life of the plant. Whole areas are frequently seen covered with 



Il6 INSECTS INJURIOUS TO VEGETABLES 

the "lice," which in a very few weeks destroy a crop. Attack 
is seldom noticed until May in the more Southern States in 
which the insect is found, and a little later in its more northern 
range. It hibernates on clover and vetch, and from these plants 
spreads by flight in April and May to peas. The females at 
certain periods produce living young. These attain maturity in 
from ten to fifteen days, and possibly in less time in the hottest 
weather. Several generations develop each year. As instance 
of the reproductive powers of this insect, Prof. W. G. Johnson's 
estimate is interesting. Females produce from no to 120 young. 
Calculating from the average number of insects produced each 
day (six), one individual would in one year become the pro- 
genitor of 423,912 "lice." 

In some instances natural enemies of the pea aphis have done 
efficient service. Seldom, however, do they destroy the insects 
sufficiently early in the season to save a crop. 

REMEDIES 

Kerosene-soap emulsion, carefully prepared and diluted with 
about twelve parts of water, and sprayed upon the plants upon 
the first appearance of the "lice," so that the leaves are wet on 
both the under and upper surfaces, has been found to be the 
most effective of the insecticides tried. A stronger solution is 
apt to scald the plant, particularly while the vines are young 
and tender. The cost of the emulsion, however, and the diffi- 
culty of under-spraying, its rapid evaporation, and the necessity 
of frequent applications, is such as to hardly warrant its use. 

Brush and cultivator method. — The peas are grown in rows 
sufficiently wide apart as to admit of a one-horse cultivator be- 
tween them. The "lice" are brushed from the plants with 
boughs of pine with their leaves on, and a cultivator follows 
down the rows immediately afterward. This method should be 
practiced in the heat of the day, when the ground is dry and 
hot, and a repetition of the brushing is necessary every three 



INSECTS INJURIOUS TO BEANS AND PEAS II7 

to seven days until the crop is ready for picking. Such "lice" 
as are not buried in the ground will be killed by the dust which 
closes their breathing pores, while a considerable proportion 
are destroyed also by the force of the brushing. Peas planted 
in rows to permit of frequent cultivation suffer much less injury 
than when sown broadcast. As soon as the last picking has 
been made infested plants should be promptly plowed under. 

Cultural methods. — Of cultural methods there is testimony to 
the value of early planting, the earliest peas seldom being in- 
fested, or at least only slightly injured. Very late plantings 
of peas for canning have also escaped ravages in some instances. 

Rotation of crops is advisable, and it is unwise to plant peas 
in successive years in the same portion of a farm, or in the 
vicinity of other leguminous plants likely 
to harbor this species. 

As this insect passes the winter on 
the plants mentioned, because peas are 
not available, it might be possible to 
use small plats of some of them as trap 
crops. Crimson clover would probably 
be best because of the early start that 
it gets in the spring. On the trap plants 
the "lice" could be killed by hand 
methods, such as brushing from the 
plants into pans, and thus large numbers Fi ^ '' 1 - -cratcy leaf hopper. 

r . . Adult - (Author's illustration, 

could be killed early in the season be- u. s. Dept. Agr.) 
fore they had opportunity to spread to peas. 

Leafhoppers of several species occur in all stages, feeding 
on the under surface of leaves of bean and cowpea, but are not 
known to be particularly injurious. The most conspicuous 
species, on account of its large size and bright colors, is the 
crafty leaf hopper (Diedrocephala versuta Say, fig. 71). Rem- 
edies have been discussed on page 86. 

Plant-bugs are often abundant on edible legumes. Of these 




Il8 INSECTS INJURIOUS TO VEGETABLES 

the garden flea-hopper (Halticus uhleri Giard) lives in great 
numbers on the leaves, puncturing them so as to cause the death 
of the tissues in small irregular white patches. In its snort- 
winged form (fig. J2, a) it resembles the black flea-beetles, which 
affect potato, alike in appearance, in the nature of its work, 




Fig. 72.— Garden flea-hopper, c, Brachypterous female; b. full-winged female. All 
much enlarged. (Author's illustration. U. S Dept. Agr.) 

and in its saltatory power. Other food plants include potato, 
pumpkin, cabbage, ornamental plants, clover and many weeds. 
Remedies are the same as for leafhoppers. Beans, peas and 
other plants subject to injury should not be planted in or near 
old clover fields. 

Nuttall's Blister Beetle (Cantharis nuttalli Say).— Blister 
beetles do much injury to leguminous food crops and are par- 
ticularly harmful to beans and peas. Nuttall's blister beetle is a 
large and. beautiful insect, variable both in color and size (fig. 
73). It is bright metallic green, the head and thorax have 
usually a coppery luster, and the wing-covers are often purple. 
It varies from a little over half to nearly an inch. Its habitat 
extends from the northern Mississippi valley region to the 
Rocky Mountains, and it is abundant from South Dakota to 
the northwest territories of Canada. It is related to the Spanish 
fly, the Cantharis vesicatoria or cantharides of commerce, has 



INSECTS INJURIOUS TO BEANS AND PEAS 



119 



the same blistering properties, and might be put to the same use. 
The beetles make their first appearance about the first of July, 
ravenously devour the blossoms and tender leaves of beans and 
other vegetables, and, if report speaks truly, they are capable 
of destroying a crop in a day. 

From the rapidity with which this insect works, poisons are 
of little value. We must, therefore, resort to mechanical meas- 
ures, and in their employment promptness and thoroughness are 





Fig. 73.— Nuttall's blister beetle. 
One-third larger than natural 
size. (Author s illustration, 
U. S~ Dept. Agr.) 



Fig. 74.— Ash-gray blister beetle. 
Female at right, twice natural size; 
male antenna at left. Greatly en- 
larged. (Author's illustration, U. S. 
Dept. Agr.) 



essential. The beetles may be destroyed by driving them into 
windrows of dry straw or similar material and burning them; 
by sweeping them into a net, such as is used by insect collectors, 
and throwing the captured insects into a fire ; or by beating 
them into specially prepared pans of water on which there is 
a thin scum of coal oil. 

The Ash-gray Blister Beetle (Macrobasis unicolor Kby.). — 
This is one of our commonest Eastern species (fig. 74), and 
although very destructive to beans and peas, is also a serious 
enemy of beets, potato, and tomato, and attacks besides sweet 
potato and some flowering plants. 

Blister beetle remedies are discussed on page 68. 



CHAPTER VIII 



INSECTS INJURIOUS TO BEETS AND SPINACH 

The recent extension of the sugar-beet industry in this 
country has been the means of bringing to notice a large number 
of insects not previously identified with that plant. Owing to 
its lesser prominence as a merchantable product, spinach is not 
grown to the same extent, and it follows that its known insect 
enemies are fewer still. With the exception of some insects 
which will be mentioned, the majority of those which live more 
or less habitually on beets and spinach feed normally on related 
wild plants, including the goosefoot, amaranth, saltbush and 
the like. During the last quarter century several insects have 
been so prominent as pests in fields of sugar-beet, that they 
have received names indicative of their beet-feeding habit, while 
some few take their common names from spinach. Of these 
are the beet army worm, beet webworm, spinach leaf-miner, 
spinach flea-beetle, beet carrion-beetle and the beet aphis. Up 
to 1907 nearly 200 species of insects have been observed to use 
beets as food. 

The greatest losses from insect attack are probably due to 
flea-beetles, but they, as well as cutworms and similar groups, 
are so irregular in their depredations that an exact estimate 
cannot be made. Different species of leaf-beetles and cater- 
pillars, other than cutworms, do more or less injury, and several 
blister beetles devour the foliage of sugar and table beets freely ; 
most forms of the last, however, usually make their appearance 
so late in the season that, although defoliation may be excessive, 
comparatively little damage is accomplished. The same is true 
of some species of grasshoppers. Two common forms of farm 
120 



INSECTS INJURIOUS TO BEETS AND SPINACH 



121 



insects, white grubs and wire worms, are at times injurious to 
the roots, and root-aphides injure the roots so as to render 
them comparatively useless. 

FLEA-BEETLES AND LEAF-BEETLES 

As flea-beetles are among the most troublesome sugar-beet 
"pests from their early occurrence and the rapidity with which 




Fig. 75. — Spinach flea-beetle, a, Beetle; b, egg mass, showing mode of escape of larva 
at right; bb, sculpture of egg; c, full-grown larva; d, pupa; e, newly-hatched larva; /, 
abdominal segment of same, a, c, d, Five times natural size; b. e, more enlarged; bb, f, 
still more enlarged. (Author's illustration, U.S. Dept. Agr.) 

they work, they may receive first mention, especially as no less 
than twenty forms have been observed attacking this plant 
Some of these are widely distributed ; others are local. Most 
farmers are familiar with flea-beetles, better known perhaps as 
"fleas," and it will be unnecessary to enter into detail in regard 
to more than one species. 

The Spinach Flea-beetle {Disonycha xanthomelcena Dalm.). — 
This flea-beetle (fig. 75) is black with a reddish-yellow thorax. 
It appears early and, like other species of its kind, works 



122 



INSECTS INJURIOUS TO VEGETABLES 



rapidly. It can be controlled in the same manner as other flea- 
beetles and leaf-beetles, and there is no doubt that if growers 
took pains not to allow chickweed and lambsquarters to spring 
up in the fields that the insect could be still more easily de- 
stroyed, as the first generation is produced on this and some 
similar weeds, and it is the second generation which attacks 
the beets. Its young, or larva, has the same habit as the adult, 
and the species frequently "cleans out" entire rows of beets 
before its appearance is suspected. 

Remedies for flea-beetles are discussed on page 65. 

The Larger Beet Leaf -beetle (Monoxia puncticollis Say). — 
Two species of native leaf-beetles are important enemies of the 
sugar-beet in the West, where they are sometimes known as 
"French bugs" and "alkali bugs." 

The larger beet leaf-beetle (fig. 76) lays her eggs on the 
under side of leaves, where they hatch in about six days, the 
young larvae commence feeding at once, continuing for nine or 




Fig. 76 —Larger beet leaf-beetle, a, Female beetle; b. eggs; c. larva; 6 , male claw; 
? , female claw. All much enlarged, claws more enlarged. (Author s illustration. 
U. S. Dept. Agr.) 



ten days, when they dig their way into the ground, and, a few 
days later, come forth as beetles. Damage is due to both the 
larvae and beetles, hundreds occurring on a single plant, which 



INSECTS INJURIOUS TO BEETS AND SPINACH 123 

is either consumed or so injured that it shrivels and dies. Since 
1897 this species has done more or less injury to sugar-beet in 
Colorado, Idaho, Utah and neighboring States, the beetles often 
occurring in swarms like blister beetles. This species resembles 
the elm leaf-beetle, but is larger and differently marked. It is 
oblong, narrow in front and dull brown while the wing-covers 
are more or less distinctly striped. 

The Western Beet Beetle (Monoxia consputa Lee). — Beets 
are much injured by this species along the Pacific Co-ast. It 





Fig 77.— Western beet beetle. 

Eight times natural size; antenna Fig. 78— Margined blister 

at left highly magnified. (Author's beetle. Enlarged. (Author's 

illustration, U. S. Dept. Agr.) illustration, U. S. Dept. Agr.) 

eats holes through the leaves, in some instances leaving only 
a network of the original leaf, and this seriously interferes with 
the growth of young plants, which are sometimes killed. This 
beetle (fig. 77) is closely related to the preceding, but is smaller, 
measuring only about one-sixth of an inch in length. 

Remedies. — These beet leaf-beetles are important enemies of 
sugar-beet culture. The general methods for the control of leaf 
and flea-beetles (see page 65) are applicable, but a few remarks 
should be added in regard to particular remedies. Paris green, 
London purple, and paragrene have all been employed against 
the larger species with apparently good results when applied 



124 INSECTS INJURIOUS TO VEGETABLES 

dry, mixed with flour, in the same manner as for the Colorado 
potato beetle. The beetles accumulate quite largely upon 
"mother" beets early in spring, which suggests that if a few 
beets be left in the ground over winter they will serve as trap 
crops for the protection of the younger plants in spring. The 
larger species practically confines its injuries to plants growing 
in or in close proximity to alkali soil. Hence such ground is 
to be avoided for the cultivation of beets. 

BLISTER BEETLES 

Blister beetles are among the most conspicuous of all beet 
enemies, and no less than n species have been observed as 
doing injury to sugar-beet alone. One of the commonest is the 
margined blister beetle (Epicauta marginata, fig. 78). The 
writer has seen entire plantings of beet almost completely de- 
foliated by it; but as a rule this and several of the other beet- 
feeding blister beetles occur too late in the season to do material 
harm, as the roots have by this time made nearly complete 
growth. This species also attacks beans, potatoes and tomatoes, 
as well as other vegetables, and is destructive to some flowering 
plants. It is most abundant in July and August. 

Remedies are the same as for other blister beetles (page 68). 

CUTWORMS AND OTHER CATERPILLARS 

When sugar-beets are cultivated over a large territory, there 
is comparatively little danger of injury from common cutworms 
which are such serious pests in the vegetable garden. Certain 
species, however, occur occasionally in great numbers, spreading 
from field to field, like the army worms, and sometimes 
sweep everything before them, as they feed upon every portion 
of the plant — foliage, flowers, stalks, and even roots. At such 
times they should be promptly destroyed. Methods of control 
employed against cutworms are considered on page 54. When 
traveling in armies cutworms should be treated as army worms 
(see p. 58). 



INSECTS INJURIOUS TO BEETS AND SPINACH 



125 



The Beet Army Worm (Laphygma exigua Hbn.).— This 
species has come into prominence since the extensive cultivation 
of the sugar-beet in the West. It is rapidly widening in distribu- 
tion, chiefly by the flight of the mature insect, a moth resembling 
the parents of the cutworms. This insect might be a still more 
injurious sugar-beet pest than is yet known, save for the fact 
that it attacks many other crops and weeds. 

The moth (fig. 79, a) is of a gray color, resembling the plain 
form of the fall army worm, to which species it is related. The 




Fig. 79.— Beet army worm, a, Moth; b, larva, lateral view; c, larva, dorsal view: a. head 
of larva; e, egg, viewed from above; f, egg, from side. All enlarged. (Author s illus- 
tration, U. S. Dept. Agr.) 

fore-wings are broader and paler, and the reniform and other 
spots as well as mottlings are more distinct. The wing expanse 
is less than an inch and one-half. The larva is striped, as 
shown at b and c. 

Remedies. — When occurring in numbers this insect can be 
controlled by means of an arsenical, but when unduly abundant, 
army worm remedies are necessary. 

The Beet Webworm (Loxostege sticticalis Linn.).— This in- 
sect is, like the preceding, of foreign origin, and is also rapidly 



126 



INSECTS INJURIOUS TO VEGETABLES 



increasing its range, and as it has developed an unusual fond- 
ness for sugar-beet it will in time become a beet pest of great 
importance. It has evidently been introduced on the Pacific 
Coast and has been found destructive as far eastward as 
Michigan and Nebraska, and has done considerable injury in 
other localities, including Canada where it was recently very 
destructive. It is cousin to the native garden webworm, which 
it resembles in general form. It is, however, darker and about 




Fig. 80.— Beet webworm. a, Moth, twice natural size; b, larva, less enlarged; e, upper 
surface of first proleg segment of larva; d, side view of same; c, d. more enlarged. 
(After Insect Life.) 

one- fourth larger. Fully expanded the wings measure nearly 
an inch, and are purplish brown in color, with darker and paler 
bands, as shown (fig. So, a). The hibernating caterpillars make 
a burrow beneath the surface of the ground and construct a 
cocoon about three times as long as themselves. A similar but 
shorter cocoon is made by the midsummer brood. 

A favorite wild food plant of this species has been observed 
— the pigweed or careless weed (Amaranthus) — and injury to 
sugar-beet has been observed in many cases where the ground 
was allowed to run to the wild plant. 

Remedies. — The, destruction of this and other weeds might 
in time lead to comparative immunity from the attack of the 
webworm. Paris green or other arsenical sprayed several times 
over the infested plants will also compass its destruction. 



INSECTS INJURIOUS TO BEETS AND SPINACH 



127 



Other kinds of caterpillars, including such well-known forms 
as the zebra and salt-marsh caterpillars, are often found in beet 
fields, but seldom in sufficient numbers to do serious injury. As 
a rule they readily yield to sprays of Paris green. 

GRASSHOPPERS 

Grasshoppers, or locusts, as well as crickets and some related 
insects, are of great importance in the West, and frequently do 
injury to sugar-beets. Many species attack this plant. 

Remedies. — The hopper-dozer is a necessary implement in our 
warfare against this class of pests, It is discussed with other 
grasshopper remedies on page 71. 




Fig. 81 — Beet leaf-miner, a, Fly; b, head of male fly; c, head of female; d> surface 
of egg, highly magnified; e, egg," /, maggot; g, head of same; /, anal segment; k, anal 
spiracles. All enlarged. (After Howard, U S. Dept. Agr.) 

LEAF-MINERS 

Hitherto insects which affect chiefly the foliage by chewing 
have been treated. We now come to a consideration of insects 



128 INSECTS INJURIOUS TO VEGETABLES 

of different habits, and among these are the leaf -miners — small, 
white maggots producing two-winged flies resembling the house 
fly. These burrow between the two surfaces of the leaves and 
form blotches termed mines. The principal species, the beet 
or spinach leaf-miner (Pegomya vicina Lint.), is illustrated 
(fig. 81). We have not as yet ascertained any perfectly satis- 
factory remedy for the leaf-miners. 

PLANT-BUGS, LEAFHOPPERS AND APHIDES 

Hordes of sucking insects, many plant-bugs, leafhoppers 
and numerous related forms are present in fields of sugar-beet 
at all times, and sometimes accomplish very considerable in- 
jury. Among the most prominent of these are the false chinch- 
bugs. 

The most satisfactory manner of keeping false chinch-bugs 
in check is by clean farming methods, destroying purslane and 
other weeds, and the cleaning up of crop remnants before 
winter, so as to leave no place for the insects to pass the 
winter. Some growers have observed that the flooding of 
fields infested by these insects forces them to leave, and the 
growing of mustard as a trap crop gives good results, provided 
the precaution is always taken to destroy the mustard before it 
runs to seed. 

The sugar-beet leafhopper (Eutettix tenella Baker) came into 
prominence as a beet pest in Utah, Idaho and Colorado in 1905, 
doing damage that year estimated at $500,000. This insect has 
become locally known as "white fly" and its injury as "blight." 
It has been noticed that late-planted beets are principally 
damaged and that early plants are less injured, and it may be 
that on this or a similar point in its life economy may hinge 
the remedy. It is worthy of remark that the species was un- 
known to science until 1900. 

For the aphides which attack sugar-beet, it is sometimes un- 



INSECTS INJURIOUS TO BEETS AND SPINACH I29 

necessary to employ remedies, as these creatures are peculiarly 
susceptible to atmospheric conditions, doing their greatest in- 
jury in cool, damp weather, and being held in nearly complete 
abeyance at times by numerous natural enemies which flourish 
in dry and even hot weather, as is very well known. In 
gardens of table beets, kerosene emulsion, pyrethrum and fu- 
migation, according to directions given on page 165, are of value. 
Practically none of these remedies can be employed on large 
fields, but are useful in small ones. Clean farming and fall 
plowing are always advisable, and crop rotation should be prac- 
ticed where possible with potatoes or similar crop. 

Two species of root-aphides do great damage. They are the 
beet aphis and beet root-aphis. 

The Beet Aphis (Pemphigus beta Doane) ruined in one year 
in a single valley upwards of 1,000 tons of beets. This was in 
Oregon. The species also inhabits Washington, and probably 
California, and it is probable that it may be reckoned among 
the important beet pests of the future. 

Owing to the large acreage in sugar-beet growing regions of 
the United States we cannot successfully control the root-aphides 
by means of insecticides. It would be supposed naturally that 
heavy flooding and plowing in fall so as to expose the insects 
to the frost might control it, but this is sometimes a failure. 
Our knowledge of alternate food plants is somewhat limited, 
but we can recommend the avoidance of beet cultivation in land 
where other plants subject to the attack of this insect have 
grown; also crop rotation. If the aphides are found at work 
only in parts of a field, they could be destroyed here with 
kerosene emulsion applied preferably just before rainfall, or by 
following the application with a flooding of water. 

Root-aphides are almost invariably associated with ants, 
which foster them and act as distributers of infestation by car- 
rying wingless forms from plant to plant. It is therefore ad- 
visable to break up the nests of ants as fast as they are found. 




130 INSECTS INJURIOUS TO VEGETABLES 

The Beet Root-aphis (Tychea brevicornis Hart, fig. 82) is 
most destructive in Colorado. It has a variety of alternate food 

plants, and we can only learn by 
experiment what are the best for 
rotation. We should avoid corn, 
sorghum, and other cereals, grasses, 
/(^^N^ Q^^ v^^ and particularly should we avoid 

U \ j| ^^ weeds, including wild grasses. Oth- 

erwise the remedies advised for the 
beet-aphis are suggested. 



^ WHITE GRUBS AND 

Fig. 82.-*, Bean rocfaphis; b, WIREWORMS 

antenna; c, tarsus. Enlarged. (After A number of forms of white _ 
Carman. ) 

grubs and of wireworms attack 
beet roots, but none appear to favor this form of food. We 
have yet to learn of severe and extensive damage by them. 

Remedies. — Among the best remedies are fall plowing, rota- 
tion of crops, clean cultivation, in particular the suppression of 
grasses, the use of potash fertilizers as stimulants to the plants 
found affected, all of these remedies acting to a certain extent 
on both forms of insects. 

In this chapter there have been considered quite briefly the 
principal forms of insects which trouble the beet-grower or 
which he may expect to meet in his fields. Several of the in- 
sects mentioned in the last four pages require additional in- 
vestigation before definite and detailed instructions can be 
furnished for their suppression. For further information appli- 
cation should be made to the Bureau of Entomology of the 
Department of Agriculture. 



CHAPTER IX 



INSECTS INJURIOUS TO CABBAGE AND 
OTHER CRUCIFEROUS CROPS 

Cabbage is peculiarly susceptible to insect attack, and there 
are probably more species of insects that injure it than any other 
truck crop. Other edible cole plants are attacked by the same 
species of insects, but as a rule suffer rather less injury. At- 
tack begins from the time the seeds commence to sprout and 
continues in the case of cabbage until the edible product is ready 
for cooking. 




Fig. 83.— Cabbage root-maggot- a. Larva; b, puparium, dorsal view; c, female fly; d, head 
of male; e, antenna. All enlarged. (After Riley, U- S. Dept. Agr.) 

ROOT-MAGGOTS 

The Cabbage Maggot (Pegomya brassicce Bouche). — The 

roots of cabbage and related cruciferous crop plants frequently 

suffer severe injury from the attack of the cabbage maggot 

(fig. 83). Young plants are most seriously affected, the mag- 

131 



132 INSECTS INJURIOUS TO VEGETABLES 

gots eroding the outer surface and boring into the interior of 
the roots, devouring the tender rootlets and frequently pene- 
trating into the lower portion of the stalk. This insect, known 
also as radish maggot, is an imported pest. It does serious 
injury throughout the northern tier of States and Canada, at- 
tacking all forms of crucifers. It is the cause of more or less 
loss to these crops each year. Since 1902 it has not only been 
exceedingly destructive, but has increased in injuriousness from 
year to year. Frequently entire crops over considerable areas 
are completely destroyed. Two or three generations of this 
maggot are indicated where it has been observed. 

REMEDIES 

The remedies prescribed for the seed-corn maggot are ap- 
plicable. In addition there are certain preventive and other 
measures for its destruction that have been found successful, 
their use being justified by the great value of cabbage plants. 

Carbolic-acid emulsion, prepared as prescribed on page 37, 
and diluted about 35 times, is applicable when this maggot oc- 
curs on radish. 

Hand-picking, although laborious, has the merit of effective- 
ness, and is useful on cabbage, although not practicable on 
radish and similar crops. It consists in pulling up the young 
plants, examining the roots for eggs and maggots, and either 
destroying the eggs and maggots by crushing with the hand or 
by washing the roots in a strong solution of soap and then 
replanting. In most cases the plants show no ill effects from 
this treatment after two or three weeks have elapsed. 

Methods of cultivation. — Comparatively little can be expected 
from various farming methods which are safeguards against 
other insects. Keeping the soil well hilled around the cabbage 
plants develops more roots, thus affording more food for the 
maggots and leaving enough roots to strengthen the plant itself. 
Crop rotation should be followed with any plants other than 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS 1 33 

crucifers or onions. With these latter it is inadvisable, as the 
same atmospheric or other conditions which induce injury by 
the cabbage maggot seem to operate in increasing the numbers 
of the onion pest, which has a similar distribution. Fall plowing 
is advisable and cabbage stumps should be removed and de- 
stroyed, especially early in the season. 

Bisulphid of carbon treatment. — In case tarred paper cards, 
which will next be described, or other preventive methods are 
not employed, bisulphid of carbon may be used. It should be 





Fig 84.— Bisulphid of carbon injector 
in use 



Fig. 85.— Tarred paper card in 
outline. One^half size. (After 
Coff.) 



applied below the root system with a special injector or syringe, 1 
taking care that the application is not made directly to the 
plants, as it is likely to kill them. A hole is made a little 
distance (3 or 4 inches) from the plant, and the injector in- 
serted at an angle, as shown in figure 84. After injecting the 
liquid the instrument should be withdrawn and the hole closed 
by packing with the foot. From a teaspoonful to a tablespoon- 
ful to each young plant, and a single application, is generally 
sufficient. 

Tarred paper cards. — The use of disks or pads of tarred paper 

1 The McGowen injector, no longer for sale, has proved very successful. 



134 



INSECTS INJURIOUS TO VEGETABLES 



for the protection of cabbage against the oviposition of the fly 
was perfected in 1889 by Mr. W. H. Goff. 

The cards are cut in hexagonal form (fig. 85), in order to 
economize material, and a thin grade of tarred paper is used, as 
y*^-^. the cards made from it are more readily placed 

L. — about the plant without being torn. The blade 

of the tool, which can be made by a blacksmith, 
is formed from a band of steel, bent in the form 
of a half hexagon, and then taking an acute 
angle, reaches nearly to the center, as shown in 
figure 86. The part making the star-shaped cut 
is formed from a separate piece of steel, so 
attached to the handle as to make a close joint 
with the blade. The latter is beveled from the 
outside all around, so that by removing the part 
making the star-shaped cut the edge may be 
ground on a grindstone. It is important that the 
angles in the blade be perfect, and that its out- 
line represent an exact half hexagon. 

To use the tool, place the tarred paper on the 
p^, 86^— Tool for en d of a section of wood and first cut the lower 
A U bcmt § one a fourth ec ^ e * nto notcnes > as indicated in figure 87, using 
size. (After Goff.) only one angle of the tool. Commence at 
the left side, and place the blade as indicated by the dotted lines, 
and strike at the end of the handle with a light mallet, and a 
complete card is made. Continue in this manner across the 




Fig. 87.— Showing how tool is used, dotted line indicating position 
of edge of tool. (After Goff) 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS 1 35 

paper. The first cut of every alternate course will make an 
imperfect carcl, and the last cut in any course may be imperfect, 
but the other cuts will make perfect cards if the tool is correctly 
made and properly used. The cards should be placed about the 
plants at the time of transplanting. To place the card, bend it 
slightly, to open the slit, then slip it on the center, the stem 
entering the slit, after which spread the card out flat, and press 
the points formed by the star-shaped cut snugly around the stem. 

A Wisconsin grower protected 7,000 plants and secured a 
splendid crop, while unprotected plants nearby would have been 
a complete failure if the maggots had not been picked off by 
hand. Others have reported similar success. One lost only 25 
plants out of 10,000 to 15,000 that he protected with the cards, 
where ordinarily he would have lost from 75 to 90 per cent, of 
the crop. 

The tarred cards are applicable to cabbage and cauliflower 
only, but it is claimed by those who have employed them that 
they are cheaper, more practicable, and more efficient than any- 
thing as yet devised for preventing the ravages of the cabbage 
maggot. Success in using them is dependent upon their being 
properly applied, to fit tightly, so that the fly is unable to obtain 
access to the stem for the deposition of her eggs. Cards must 
be renewed and their use continued for each maggot year to be 
effective. 

Coverings and hellebore. — Some success has also been attained 
by covering young plants in seed-beds with netting and by ap- 
plying hellebore about the roots. 

The Seed-corn Maggot (Pegomya fusciceps Zett.). — This 
species, previously considered on page 106 on bean and pea 
insects has been identified with attack to cabbage, turnip and 
radish on numerous occasions and in many localities. When 
occurring on such plants it should be treated in about the same 
method as the cabbage maggot. 



I36 INSECTS INJURIOUS TO VEGETABLES 

CABBAGE WORMS 
The Imported Cabbage Worm (Pontia rapce Linn.). — This is 
the worst of all cabbage pests and one of the most important 
of all truck insects. It is altogether too well known through- 




-' d 

Fig. 88.— Pontia rapae. a, Female butterfly; b, egg; c, larva on cabbage leaf; d, sus- 
pended chrysalis, a, c, d, Slightly enlarged; b, more enlarged. (Author's illustration, 
U.S.Dept. Agr.) 

out North America and Europe, and the white butter- 
fly is quite generally recognized as its parent. The cater- 
pillar is velvety green and measures, when full grown, about 
an inch and a quarter, presenting the appearance shown in 
figure 88, c. The butterfly has a wing expanse of nearly two 
inches, and is white, marked with black near the tips of the 
fore-wings. The female (a) has two conspicuous black spots 
on each fore-wing, the male has only one. This cabbage worm 
is the bane of every cabbage-grower, and the dread of every 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS 1 37 

careful cook and housewife. It begins work early in the season, 
when the principal damage is usually accomplished, and after 
riddling the outer leaves, attacks the more tender inner leaves 
as they form, frequently secreting itself in the heads, which 
are made most unsightly by its excrement. This species was 
first observed in the United States in 1865 and in about a score 
of years it had invaded nearly every state and territory in our 
domains. 

All cruciferous crops, but particularly cabbage and cauli- 
flower, are attacked, as are also nasturtium, mignonette and 
some allied plants. The butterflies are on the wing from early 
morn till dusk. As early as March they can be seen flying about 
cabbage fields and they continue until after severe frosts. The 
observed egg period is from 4 to 8 days. The larva eats 
voraciously and grows with rapidity, attaining full growth in 
from 10 to 14 days after hatching. The summer-time chrysalis 
period is from 7 to 14 days, but the last chrysalides remain 
undeveloped until the following spring. The life cycle has 
been traced from between 22 days to five weeks. Even in New 
England this species is credited with being triple brooded, but 
in the District of Columbia and vicinity there must be one or 
more additional generations, and there is a possibility of still 
more in the extreme South. 

A natural enemy of this species, Pteromalus puparum, is 
shown in figure 89, and a "worm" parasitized by Apanteles 
glomeratus is illustrated by figure 90. 

REMEDIES 

In treating this species it should be borne in mind that other 
"worms" and pests are more often present than otherwise. 

Arsenicals. — The best remedy is Paris green applied, prefer- 
ably as a spray, at the rate of about one pound of poison to 
150 gallons or less of water, and it should be used when plants 
are first set out, to insure its reaching the young "worms" be- 



138 



INSECTS INJURIOUS TO VEGETABLES 



fore they have burrowed far into the heads. Other applications 
should follow frequently, as required, and can be made with 
safety until the heads are about half formed, and even later, as 
the poison, under ordinary circumstances, disappears from the 
plants two or three weeks after being applied. 

Bran mash is, according to the testimony of some, successful 
against cabbage worms. It is prepared in the same manner as 
for cutworms and grasshoppers. See page 55. 

Kerosene emulsion is not as efficient as arsenicals, because 




Fig. 89.— Pteromalus puparum. Female 
Highly magnified. (Author's illustra- 
tion, U. S. Dept. Agr.) 



Fig. 90.— Parasitized cabbage worm (Pontia 
rapce), showing cocoon mass of Apanteles 
glomeratus below. (Author, U. S. Dept. 
Agr.) 

it is necessary for this spray to come into direct contact with 

the "worms." 

Pyrethrum has the advantage of not being poisonous to 
humans, but is said by some cabbage growers to discolor the 
leaves, and if its use is not continued at frequent intervals the 
"worms" recover. It is more expensive than remedies that have 
been mentioned. 

Hot water at a temperature of about 130 F. does practically 
no harm to plants and destroys all insects with which it comes 
in contact. 

Clean cultivation and trap crops. — If united effort in clean 
farming could be secured, together with the use of arsenicals, 
the losses due to the ravages of this and other leaf-feeding 
cabbage pests might be largely averted. The practice of leaving 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS I39 



cabbage stalks in the field after the crop has been secured is 
reprehensible. Remnants should be destroyed, with the exception 
of a few left at intervals through a field as traps for the females 
for the deposition of their eggs. These plants should be freely 
poisoned with arsenicals, so that the last generation will not 
develop. 

The Southern Cabbage Butterfly (Pontia protodice Boisd.).— 
Before the advent of the imported cabbage butterfly, the present 
species was the occasion of considerable injury, particularly 





[HUH 

Fig. 91.— Southern cabbage butterfly 
worm. (After Riley) 






Fig. 92.— Potherb butterfly. Adult above, 
larva below. (After Harris) 



southward. Of late it has disappeared in many regions, but 
occasionally makes its reappearance for a limited period. In 
many respects it resembles the preceding, and the male as it is 
seen flitting lazily through cabbage fields and gardens would * 
never be recognized as" distinct from the more injurious form. 
The "worm" (fig. 91) varies from pale to dark blue or green, 
is striped with yellow and covered with black spots bearing 
black hairs. 

Remedies. — The treatment is the same as for the preceding. 

The Potherb Butterfly (Pontia napi Linn.).— This butter- 
fly is found in the more northern and eastern portions of 
North America, and is distinguished from others attacking cole 
crops by its nearly uniform white wings without spots. The 
larva (fig. 92) is uniform pale green, and resembles the cab- 



140 



INSECTS INJURIOUS TO VEGETABLES 



bage leaves on which it feeds. It devours the pulp on the lower 
surface, often leaving the veins intact. 

This species has evidently been decimated in the same man- 
ner as the southern cabbage butterfly by the foreign invader, 
Pontia rapes, and is now seldom found save on wild plants. 

Remedies are the same as for the imported cabbage butterfly. 

The Cross-striped Cabbage Worm (Evergestis rimo salts 
Guen.). — Thus far have been considered only the "worms" 
produced by butterflies. The species figured and those which 




Fig, 93.— Cross-striped cabbage worm, a, Moth; b, egg mass; c, sculpture of egg; 
d 'worm ' ; e, cocoon, a, d, e, Twice natural size, b, c, more enlarged. (Author's 
illustration, U. S. Dept. Agr.) 

follow are all the progeny of moths. This "worm" injures cab- 
bage and its varieties in nearly the same manner as does the im- 
ported cabbage worm, attacking the heads and digging deeply 
into, and eating out, the hearts. While plants are tender this 
destroys them for the market or table. This species is as a rule 
less injurious to other crucifers (fig. 93). 

Remedies. — The remedies advised as best for the imported 
cabbage worm are equally applicable to this species. 

The Common Cabbage Looper (Autographa brassicce Riley). 
— Late cabbage particularly southward is much subject to injury 
by the looper or cabbage "plusia" which is, next to the imported 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS I4I 

cabbage worm and the harlequin bug, our most important insect 
enemy of cruciferous crops. It is unusually voracious, devel- 
oping rapidly, but is kept under partial control by natural in- 
fluences, and therefore subject to extreme fluctuation in num- 
bers, doing great damage for one or more seasons in some 
localities, and remaining absent from them for a number of 
succeeding years. 

The insect derives its name from the peculiar habit of its 
larva of "looping" like a measuring worm, due to the lack of 
legs on the third and fourth joints of the abdomen. The moth 
which produces it is shown in figure 9, a. The "looper" is at 
first a pale-green, fragile-looking creature, and varies in 
color when mature, being strongly marked with white lines, 
shown in figure 9, c. It constructs for pupation a white, gauzy 
cocoon, d, which is usually attached to the broad surface of 
a leaf. The cabbage looper is well distributed throughout that 
part of the United States lying east of the Rocky Mountains, 
and is more destructive in the South than in the northern States. 
It is most troublesome to cabbage, but affects all crucifers and 
at times does great injury to peas, beets, celery and lettuce, and 
feeds also on tomato, potato and less frequently on asparagus 
and clover. It sometimes does damage to carnation, mignonette, 
and German ivy in greenhouses. 

The species is apparently three-brooded on Long Island and 
in the District of Columbia, and hibernation takes place chiefly 
in the pupal stage. Few individuals survive the winter north- 
ward, but the propagation of the species is so rapid that by the 
time autumn is reached great numbers of loopers are produced 
which do much damage to crops in cultivation at this time. This 
insect is very susceptible to diseases and to parasitism. A par- 
asitized looper is shown by figure 94. 

Methods of Control employed for other cabbage worms are 
useful against loopers. Remedial measures should be continued 
with persistency at frequent intervals in order to insure sue- 



142 INSECTS INJURIOUS TO VEGETABLES 

cess, and arsenicals should be applied when possible to the lower 
surface of the outer leaves to destroy all the insects. If the 
first generations could be killed off there would be less difficulty 
in keeping the insect in subjection. Paris green mixed with 
lime or other diluent has been used dry with some success, but 
is less efficient than for the imported cabbage worm. Dry ap- 
plications do not reach the lower surface, hence a spray is 
preferable. The larger loopers eat through the leaves, but when 
they find anything distasteful they cease feeding and search for 
tissue that has not been poisoned. After rainfall eggs hatch 
and the poison having been washed away the larvae continue 
feeding. Sirrine obtains good results with resin-lime mixture. It 
requires about two hours to make this mixture, and considerable 




Fig. 94.— Cabbage looper parasitized by Copidosoma Vuncatelhx Slightly enlarged 
(After Riley, U. S. Dept. Agr J 

care is necessary in its preparation; but when crops are grown 
on a large scale it might pay to use this remedy. It has the 
advantage of being more adhesive than a Paris green spray, 
remaining on the under surfaces as well as upper leaves and 
requiring two or three heavy rains to remove all of it, even on 
the exposed portions of leaves. Arsenate of lead has similai 
adhesiveness, and as it has given good results in experiments 
on a small scale it should receive further tests. 

The Imported Cabbage Webworm (Hellula undalis Fab.). — • 
As if the cabbage-grower did not have enough "worms" with 
which to contend a new species has recently appeared in the 
South, and there is now the threatened danger of its introduc- 
tion farther north in the same manner as has happened in the 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS I43 

case of the cabbage looper and harlequin cabbage bug. The 
species under consideration, the imported cabbage webworm, 
should it increase in destructiveness and enlarge its area, bids 
fair to become a troublesome species, as it is difficult to treat. 
The moth (fig. 95, a) is gray, with the fore-wings mottled 
with black, white and brown. The expanse of wing is about 




Fig. 95.— Cabbage webworm. a, Mature moth; b larva, lateral view; c, larva, dorsal 
view; d. pupa All three times natural size. (Author's illustration, U. S. Dept. Agr-) 



five-eighths of an inch. The mature larva (fig. 95, b, c) is a 
little more than half an inch long, in color dull yellowish-gray, 
striped with broad, brownish-purple longitudinal bands. The 
moth is described as laying her eggs in the "bud" of cabbage, 
or turnip, and the larva soon after hatching spins a web over 
itself, leaving a hole for egress. From the protection afforded 
by this domicile the larva feeds, retiring into the web when its 
hunger is appeased. When larvae are particularly numerous 
three or four days suffice for the destruction of a turnip or cab- 
bage patch, the plants rotting, or in the case of turnip failing 
to develop roots, and this with their excrement which adheres 



144 INSECTS INJURIOUS TO VEGETABLES 

to the plants, forms a more or less perfect place of concealment 
for them. 

Remedial Measures. — A spray of Paris green applied as soon 
as the larva hatches serves in great measure to control it. Clean 
cultural methods should be persistently practiced, and every bit 
of refuse material, particularly cabbage stalks and weeds, should 
be raked up into piles and set afire by adding, if necessary, dry 
straw to aid in their ignition. Kerosene emulsion, properly 
prepared and applied sufficiently often to insure a permanent 
odor, should be effective in preventing egg laying and will also 
destroy other insects with which it may come in contact. 

The Diamond-back Moth (Plutella maculipennis Curtis). — One 
of the minor enemies of cabbage is the larva of the imported 
diamond-back moth or "cabbage plutella." It is smaller than 
any of the preceding, and as a rule its injuries are much less 
conspicuous. Occasionally, however, it becomes sufficiently 
numerous as to be quite troublesome. Its minute active cater- 
pillar may be found on cabbage everywhere, and in this stage 
as well as in pupa, when it rests in a beautiful white, lace-like 
cocoon attached to the surface of cabbage leaves, it is familiar 
to observing persons. Attack is usually confined to the outer 
leaves, the larva feeding generally on the lower surface and 
not eating through, as with the larger looper and some other 
worms. At times, however, leaves are riddled with holes and 
much of their substance devoured. 

The moth (fig. 96, /) is gray and distinguished by the black- 
marked fore-wing. The wing expanse is about three-fifths of 
an inch. This insect is found during winter on old cabbage 
stalks, hibernation taking place normally as pupa, although 
adults also occur as late as December. Two or three genera- 
tions are produced in the more northern States, and farther 
south four or five broods occur during a season. In the extreme 
South the insect occurs throughout the year. 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS I45 

Remedies. — The simpler cabbage worm remedies are suffi- 
cient in ordinary cases. Pyrethrum is valuable as is also kero- 
sene emulsion, but Paris green, unless applied as an under- 
spray, which is difficult with most cruciferous crops, is reported 
not so effective. 

Cutworms will attack cabbage, turnip, and similar plants 
when available, and there are a number of caterpillars, other 
than those which have been considered, which do great damage 




Fig. 96.— Diamond-back moth, a, Larva; b, c, segments of same; d, pupa; e, pupa in 
cocoon; /. h, moth; g, wings of dark form of moth; 1, last segment of pupa. All en- 
larged. (After Riley, U. S. Dept. Agr.) 

to these crops. When cutworms become abundant late in the 
season, plants are damaged in the same manner as by the 
imported cabbage worm, by eating the more tender portions and 
penetrating into the hearts. Severe injury is often reported, 
e. g., in one garden only 30 plants out of 600 escaped, while 
it is not uncommon to lose half or more of the plants early in 
the spring. The fall army worm, salt-marsh caterpillar and 
"woolly bears" frequently attack* cole crops, and the first 
mentioned when numerous does damage of great seriousness. 
The zebra and clover caterpillars appear to favor these crops 
among others grown in gardens, and the garden webworm also 
affects them. These species are treated in preceding chapters. 



146 



INSECTS INJURIOUS TO VEGETABLES 



FLEA-BEETLES AND LEAF-BEETLES 

An unusual number of flea-beetles are reckoned among 
enemies of cruciferous crops. No less than seven species (of 
Phyllotreta) are more or less attached to this class of plants 
and although like other flea-beetles they are as a rule only 
periodically troublesome, they are in their abundant seasons 
foes of. no little importance. The characteristics of flea-beetles 
have been described on page 63. The cabbage-feeding forms 
are mostly quite minute, none measuring more than an eighth 
of an inch. 

The Striped Turnip Flea-beetle (Phyllotreta vittata Fab.). — 
The commonest and most destructive flea-beetle living on 

cruciferous crops is the species 
above mentioned. It is found 
throughout the warmer months, 
and attacks most crucifers, cul- 
tivated and wild. As it is sub- 
ject to great fluctuation in num- 
bers, it cannot be compared to 
the imported cabbage looper or 
harlequin bug, yet it is capable 
of severe injuries and crucifer- 
ous crops are seldom free from 
it within its range, which is 
extensive. The beetle (fig. 97, 
b) is polished black in color, 
and each wing-cover is ornamented with a broad, wavy band 
of pale yellow. 

This species is indigenous to the Atlantic region, where it is 
most abundant, but has been diffused by commerce, until now 
it is found in most States and Territories from Maine to the 
Gulf and Pacific States. 

Remedies. — When cabbage and other crucifers are treated 
with arsenicals for "worms" no further remedy is necessary 




Fig. 97-— Striped turnip beetle, a, larva 
b, beetle. (Riley, U. S. Dept. Agr.) 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS 1 47 



for flea-beetles. It adds to the effectiveness of Paris green, 
however, to use Bordeaux mixture as a diluent, as the latter 
in addition to being a fungicide is a powerful deterrent of 




Fig. 98.— Water-cress leaf-beetle (Phasdon aeruginosa), a. Adult; b, larva; d. pupa 
Enlarged six times. (Author's illustration, U. S. Dept. Agr.) 

flea-beetles. See page 65 on remedies for leaf-beetles and 
flea-beetles. 

The Water-cress Leaf-beetle (Phcedon ceruginosa Suffr.) 
has been reported injurious to water-cress since 1903. It is a 
small, metallic blackish beetle (fig. 98) and with the water-cress 
sowbug (figured on page 4) is a pest on 
the plant from which they have both re 
ceived their English name. 1 

The Western Cabbage Flea-beetle (Phyl- 
lotreta pusilla Horn.). — In some of the 
western States not yet inhabited by either 
of the preceding there is a smaller, dark- 
colored flea-beetle which sometimes does 
great damage to crucifers and many other 
crops. 

This flea-beetle is of a uniform deep Fi 99.— western cab- 
polished olive-green color, and the surface ba s e flea-beetle. Much 

, , T , enlarged. (After Riley, 

is irregularly punctate. It measures about u. S. Dept. Agr.) 
seven-hundredths of an inch in length. It 
ranges from the Dakotas to Mexico, and westward to Southern 
California and is often found in great numbers. 

1 Information concerning both species is furnished in Bui. No. 66, Pt. II, 
Bu. Entom., U. S. Dept. Agr. 




148 



INSECTS INJURIOUS TO VEGETABLES 



Remedies. — Owing to the peculiarity of this species of con- 
gregating in immense numbers and doing great damage in a 
short time, immediate steps for its suppression must be taken. 
Remedies advised for the striped turnip flea-beetle are 
applicable. 

PLANT-BUGS AND APHIDES 

The Harlequin Cabbage Bug (Murgantia histrionica Hahn.). — 

From southern New York and Ohio southward, late cabbage 

and other cole crops sometimes suffer severely from a gayly 

colored plant-bug variously known as the calico back, fire bug, 







Fig. 100.— Harlequin cabbage bug- a. Young; b, half grown; c, d, egg cluster; e, same 
from above; /, g, adult, c, f, g, Natural size; a, b, slightly enlarged; d, e more en- 
larged. (After Riley.) 

and terrapin bug, as well as harlequin cabbage bug. It is the 
most destructive cabbage pest of the South, and second only 
to the imported cabbage worm as an enemy to the cole crops 
of our country. It is a native of Mexico and Central America 
and since its discovery in Texas in 1866 its dissemination north- 
ward and eastward has been rapid, until at one time it threatened 
to overrun southern portions of New York and New England, 
Ohio and States farther westward. The harlequin-like ornamen- 



tation of the insect is shown in figure 100, /. 



the dark 



portions are shining black or dark blue and the lighter portions 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS I49 

bright yellow or red. The eggs (d) are beautiful objects, 
looking like miniature white barrels bound with black hoops, 
and with black spots set in the proper place for bung-holes. 

This insect accomplishes its work of destruction by sucking 
the sap from leaves and veins of cabbage and other crucifers, 
the affected leaves wilting, withering and dying as if fire- 
swept — whence the name "fire bug." Half a dozen mature 
insects suffice to destroy a small plant in a day. This is a 
pest which, if permitted to have its own way, is almost certain 
to destroy a portion, and if sufficiently numerous, all of the 
fields which it infests, and the writer has seen in the vicinity of 
the District of Columbia, in Maryland and Virginia many fields 
in successive years from which not a single good cabbage could 
be cut, and has observed equal injury to horseradish and some 
other crucifers. Toward the end of the season and in early 
winter the mature bugs are still afield, seeming loath to seek 
shelter from the cold. When cruciferous crops have become 
exhausted they attack almost any form of vegetation. 

Preventive and Remedial Measures. — The difficulty of de- 
stroying this insect with contact poisons such as kerosene- 
soap emulsion, which are practically inert against the adults 
and only partially effective on the youngest nymphs, necessi- 
tates the use of preventives to compass this end. The most 
important is clean farm practice. The practice of leaving 
cabbage stalks and other cruciferous plants in the field late in 
autumn and early winter, or of allowing cruciferous weeds to 
grow up, or, in fact, allowing any sort of debris to accumulate, 
serves to protract the life of this insect by affording it food 
or quarters for protection against the cold. It is inadvisable 
to plant crucifers in the vicinity of outhouses and barns, as 
the bugs use such places for passing the winter. 

Some of the insect's food plants may be left, after cropping, 
at intervals throughout fields to attract the bugs in the fall, 
and here they may be killed with crude kerosene, by mechanical 



15° 



INSECTS INJURIOUS TO VEGETABLES 



methods, or piles of rubbish may be left to attract them where 
they can be burned. 

The best remedy, however, and one that should be put into 
operation by every southern cabbage grower, is the planting of 
an early crop of mustard, radish, rape, or kale as a lure for 
the first appearing bugs. Overwintered bugs appear from 
March to May. They appear to prefer for the first deposition 
of their eggs the plants that have been mentioned, though 
cabbage may be available. On these the insects are killed by 
kerosene or by hand, as, for example, by capture with a hand 
net, or by burning the traps when these are of no value as 




Fig. 101.— False chinch-bug. a, Leaf showing punctures; b, last nymph stage. 
c, adult, a, Natural size; b, c much enlarged. (After Riley) 



food. If the first generation is generally done away with, few 
insects fly from other quarters, and injury is largely prevented 
for an entire season. 

The False Chinch-bug (Nysius angustatus Uhl.). — The false 
chinch-bug, although a general feeder, appears to be somewhat 
more attached to turnip, cabbage and similar crops, but also 
injuriously affects potato, beets, lettuce, the vine, apple, grass 
and strawberry. It derives its name of false chinch-bug from 
its being frequently mistaken for the true chinch-bug, to 
which indeed it is related. The adult is grayish brown and 
of the appearance shown in figure 101, c. The hemelytra or wing- 
covers are more or less transparent. The length is about 
one-eighth of an inch. In distribution it extends from New 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS 15I 

Hampshire to the Gulf, and westward to the Pacific States. 
At a of figure 101 is represented the appearance of a leaf 
of potato showing the minute, rusty circular specks where the 
beak of this bug has been inserted. The false chinch-bug 
frequently occurs in such numbers as to attract general atten- 
tion. The bugs crowd together on a plant in the same manner 
as do the chinch-bugs on corn, and the harlequin bugs on 
cabbage; and as they also feed by suction, they soon exhaust a 
plant by depriving it. of its juices, which in time causes it to 
wilt and die. This is an active bug, and when alarmed on 
warm days, the winged individuals readily take to flight, arising 
in swarms. It. is subject to the same atmospheric influences 
as the chinch-bug, and damp, rainy weather is unfavorable to 
its development. It has been surmised that there are two or 
three generations a year and that the insect hibernates mainly 
in the perfect state under rubbish of different sorts. 1 

Remedies. — The best way of controlling this bug consists in 
the keeping down of purslane, a favorite food plant, the 
careful cleaning up and burning of all trash before winter, the 
collection of the bugs when they occur in numbers in pans or 
pails filled with water and a thin scum of kerosene, and the 
free use of 10 per cent, kerosene emulsion. 

The Cabbage Aphis (Aphis brassicce Linn.). — In seasons when 
atmospheric conditions favor its development this insect, which 
is also known as the "cabbage louse", 2 can be exceedingly 
troublesome ; indeed, were it not for its susceptibility to many 
natural enemies, it would always be a pest of the highest im- 
portance in localities adapted for its increase. This species 
affords a most excellent example of the usefulness of natural 
enemies. A vast number of insects that prey on aphides 

1 A related bug (Nysius minutus Uhl.) very nearly resembles the preceding 
in appearance and in habits, and may be controlled by the same methods. 

2 A similar aphis (Rh op ah sip hum dianthi Schr.) , with somewhat similar habits, 
is also very injurious to cole crops and may be controlled by about the same 
means. 



152 INSECTS INJURIOUS TO VEGETABLES 

attack it, and in many regions hold it down to moderate num- 
bers save in exceptional seasons. In dry, warm weather the 
insect enemies are most active, while in cooler dry weather 
they are less efficient and then the plant-lice frequently gain 
the ascendency, to the detriment of the cabbage crop. 

Its first appearance is usually noticed in June, and it remains 




Fig 102.— Cabbage aphis. 0, So-called '' male " ; b, wingless viviparous female. Greatly 
enlarged; natural size indicated by small outlines. (After Curtis) 

until quite cold weather. In the District of Columbia the writer 
has observed this species active as late as the middle of Decem- 
ber, mostly, however, at this time, in the hearts of cabbage, 
where the aphides had crawled for protection. 

Practically the same or related insect enemies of the pea 
aphis which have been mentioned in preceding pages attack 
the cabbage aphis. 

Remedies. — The cabbage aphis can be controlled by much the 
same remedies as advised for the melon aphis (page 165), the 
free use of pyrethrum applied by a bellows at any stage of the 
growth of the cabbage or other plant; or by kerosene emulsion, 
which is of value when the plants are young and until the 
heads begin to complete their growth. Soap solutions may be 
used if preferred, those known as whale-oil soap, made of fish 
oil, and potash soaps, made from caustic potash, being the best. 
A strong stream of water directed upon the plants from a 



INSECTS INJURIOUS TO CABBAGE AND OTHER CROPS 1 53 

syringe, hose or spraying machine is often of service in check- 
ing the work of this insect. Application of remedies should 
be made upon the first appearance of the insects. Clean cultural 
practice should be observed. 

MAGGOT LEAF-MINERS 

The leaves of cabbage, turnip, radish and other crucifers 
are subject to the attack of minute maggots which manifest 
their presence by whitish blotches of larger or less extent, 




Fig. 103.— Imported turnip leaf-miner, a. Larva; b, puparium; c, adult; d> antenna of fly; 
e, work in radish leaf. Natural size; all. others enlarged. (Reengraved after Coquil- 
lett, U. S. Dept. Agr.) 



termed mines. If a leaf be held toward the light the maggot 
can be seen at work between the surfaces. Four species of 
leaf-miners commonly affect crucifers. These insects are not 
as a rule very destructive, but they kill off leaves here and 
there, thus weakening the plants, and rendering them more 
liable to disease and to injury by other insects. Sometimes, 
however, they destroy whole plants. Attack is more apparent 
on young plants and is easily recognized. One of the commonest 



154 



INSECTS INJURIOUS TO VEGETABLES 



of these insects is the imported turnip leaf-miner (Scaptomyza 
flaveola Meig.) shown in figure 103. 

Remedies. — These leaf-miners are not very injurious to large 
interests. In small gardens they can be controlled by clipping 
the infested leaves as soon as the mines appear and destroying 
them. 




Fig. 103x.— A young cabbage looper, highly magnified. (Author, U- S. D#pt. Agr,; 



CHAPTER X 

INSECTS INJURIOUS TO CUCUMBER, MELON 
AND RELATED PLANTS 

If we except cabbage no vegetable crops suffer more from 
the ravages of insects than do the cucurbits — squashes, cucum- 
bers and melons. They are subject to attack from the time 
the seed is planted and after it has sprouted until the fruit 
is ripe for market. Injury is not effected by so many species 
of insects, as in the case of cabbage, less than a score of 
distinct forms being commonly identified with damage, but of 
these nearly a dozen are highly injurious, and half as many 
from their extensive distribution and destructiveness are of 
the greatest importance. It is no uncommon sight to see four 
or five distinct species on a single plant, and several others in 
the same field. 

The seeds are attacked in the ground by a maggot which eats 
into them and prevents germination. After the seed has 
sprouted the plant becomes the prey of the striped cucumber 
beetle, the most troublesome of all cucurbit-feeding insects. 
Such plants as are so fortunate as not to be attacked by this 
beetle, cutworms and some few other "general feeders" may 
next encounter the squash bug and then the squash-vine 
borer. The latter severs the vine or injures it so that it wilts and 
dies. It is next to impossible in many portions of the United 
States to find cucurbits that are wholly free from the melon 
aphis which feeds by absorbing vegetable juices by suction. 
After the plants have escaped the insects above enumerated 

155 



156 



INSECTS INJURIOUS TO VEGETABLES 



they are still liable to injury from others and more especially 
from the pickle worm and melon caterpillar which bore into the 
fruit and render it unfit for market. 

Cucurbits grown under glass are subject to injury by four 
important pests : the striped cucumber beetle, melon aphis, 
greenhouse white fly and onion thrips. 

The Striped Cucumber Beetle (Diabrotica vittata Fab.). — 
With the first appearance of cucumber, squash and melon plants 




9> 

* d e 

Fig- 104— Striped cucumber beetle, a, Beetle; b, larva; c, pupa; d, egg; e, sculp- 
ture of egg. (Author's illustration, U. S. Dept Agr.) 

early in the season, often before they are above ground, they 
are attacked by the striped cucumbar beetle, often called the 
"striped bug" and "melon bug." 

The beetle measures about two-fifths of an inch in length. 
Its color is yellow above, with black head and elytra longi- 
tudinally striped, as figured (fig. 104). The egg is lemon yel- 
low and of the appearance shown, where the sculpture is also 
illustrated. The larva is a slender, white, worm-like creature, 
with brown head, anal and thoracic plate. When mature 
it measures about three-tenths of an inch, this being about 
ten times its width. The species is indigenous and inhabits the 
entire eastern United States. 



INSECTS INJURIOUS TO CUCUMBER, MELON, ETC. I57 

The principal injury is effected by the hibernated beetles 
devouring the tender plants before they have fairly started. 
The beetles are also destructive to older plants, by eating the 
leaves and gnawing the rind of stems and the fruit, while the 
larvae cause injury through their pernicious work at the roots. 
Still another form of mischief is due to the beetles in acting 
as carriers of the insidious bacterial disease "cucurbit wilt." 

The beetles usually make their appearance in April or May, 
feed on flowers or other vegetation, and when cucurbits are set 
out attack and injure them as previously described. Eggs are 
deposited soon after the host 
plants are well above ground, 
and on leaf-stalks just below the 
surface of the ground. The 
larval period is passed in the 
earth, about the bases of the 
stalks, and larvae may be found 
within the stems under as well 
as above ground, and there 
is an active stage of about a 
month's duration in which the 
larvse working in numbers have Fig- 105- Ceiatoria diabroticx. Fiypara- 

, .... , site of cucumber beetles. Much enlarged. 

ample time for injuring the (Author's illustration, U. S. Dept.Agr.) 

vines. 

Toward the end of the season the beetles congregate under 
stems, prostrate plants and withered leaves of cucurbits, as 
many as sixty individuals assembling about a single plant, and 
later they seek other places of shelter. Hibernation near 
Washington evidently begins during the first cold nights of 
October. 

Great numbers of this insect are destroyed by a dipterous 
parasite, somewhat resembling a small house fly, and known 
as Celatoria diabroticce Shim. (fig. 105), which develops as a 
maggot within the beetle, which it destroys when it issues. 




158 INSECTS INJURIOUS TO VEGETABLES 

REMEDIES 

How to control this cucumber beetle is one of the hardest 
propositions to solve. Poisons will destroy the beetles when they 
occur in moderate numbers, but are not entirely efficacious 
when they are most abundant, hence recourse must be had to 
preventives and repellents, and to farm practice. 

Coverings. — To prevent injury to young plants coverings are 
used. A cheap frame may be made by cutting a barrel hoop in 
two so as to form two semicircles, which are placed at right 
angles to each other, and the lower ends inserted in the ground 
with the curve uppermost. This is then covered with gauze or 
similar material, held in place so to prevent the beetles work- 
ing through or under it. 

Early planting, etc. — Where no covering is used it is advisable 
to start plants under glass, or to plant the earliest varieties and 
set them out as soon as possible so as to have the plant well 
established before the appearance of the beetles. The setting 
out of late varieties should be postponed until after the first 
appearing beetles have laid their eggs and dispersed. A cer- 
tain degree of relief follows the planting of an excess of seed 
so as to distribute attack. After the first danger is passed the 
hills are thinned out to the desired number. 

Clean farming and trap plants. — Much injury from this and 
other cucurbit pests would be prevented by more attention to 
clean methods of cultivation. As soon as a crop is harvested 
the vines should be covered with straw or other inflammable 
material and burned, and certain plants should be left here 
and there throughout the fields, so that such insects as may not 
be reached by the fire will concentrate on them where they can 
be destroyed with strong kerosene emulsion or Paris green. 
As traps for the last generation it would be wise to plant late 
or to use later varieties. Some exemption may be attained by 
growing beans with cucumbers in alternate rows. The beans 
are planted before the cucumbers and the beetles congregate 



INSECTS INJURIOUS TO CUCUMBER, MELON, ETC. 1 59 

on the beans and, having an abundance of food, do not attack 
the young cucurbits. 

Driving, etc. — In some sections "driving" is practiced. Air- 
slaked lime is dusted over the plants with the wind and the 
beetles fly before it to the next patch where similar methods 
have to be employed. Another remedy is to dust the majority 
of plants with sifted ashes, road dust or plaster, and cover 
those which are undusted with an arsenical, in the proportion of 
one-fourth of a pound to about 40 gallons of water. The 
beetles are thus driven to concentrate on the clean plants, where 
they are killed by the poison. 

Refuse tobacco dust sprinkled on the hills when the soil is 
moist acts as a repellent and as a fertilizer and mulch for the 
plant. Applications must be renewed when rainfall necessitates. 

Pyrethrum and other insecticides dusted on the plants are 
useful, but expensive. Paris green and other arsenicals applied 
dry as for potato beetles are valuable, but all poisons must be 
renewed frequently and are not generally to be relied upon 
when the beetles are exceedingly numerous. In case Bordeaux 
mixture is used as a protection against fungous diseases, Paris 
green Should be added, as it necessitates little additional trouble 
and the mixture will prove more effective than either when 
used alone. 

Stimulating growth. — A considerable degree of exemption 
from injury accrues from the stimulation of a crop by heavy 
manuring, or the use of mineral fertilizers and frequent 
cultivation. 

The Twelve-spotted Cucumber Beetle (Diabrotica 12-punctata 
01.). — This beetle will be considered at length in the dis- 
cussion of insects affecting sweet corn. In exceptional sea- 
sons it does nearly as. much injury locally to cucurbits as the 
striped cucumber beetle, with which it is nearly always asso- 
ciated. At such times, the same remedies should be employed. 



i6o 



INSECTS INJURIOUS TO VEGETABLES 



The SquasTi Ladybird (Epilachna bore alls Fab.). — The 
leaves of squash, pumpkin and the other cucurbits are often 
found showing numerous wilted and eroded circular or semi- 
circular spaces. The source is not far to seek, and can readily 
be traced to the squash ladybird and its larva. This insect is 
of the characteristic hemispherical ladybird form. It is ochra- 
ceous in color, marked with rounded black spots, as shown in 
figure 1 06, c. This is one of our largest ladybirds, measuring 
about one-third of an inch. The larva is yellow and covered 




a k ° 

Fig. 106.— Squash ladybird, a, Larva; b, pupa; c, beetle; d, egg; e, surface of same. 
a, b, c. Three times natural size; d, four times; e, highly magnified. (Author's illus- 
tration, U. S. Dept. Agr.) 



with spines arranged in six rows except on the first thoracic 
segment, where there are four (a). 

This is an indigene, ranging from South America to Maine 
and Canada. It is essentially an eastern form, occurring 
abundantly along the Atlantic seaboard. 

The singular habit of the larva and beetle of feeding within 
a circumscribed space, as previously noted, is evidently char- 
acteristic of this genus of ladybirds. It first marks out a 
circle, or if it is feeding on the edge of a leaf a more or less 
complete semicircle, thus enclosing a portion within which it 
feeds. The larva lives on the lower and the beetles on the 
upper surface, but the latter may often be found on the under 



INSECTS INJURIOUS TO CUCUMBER, MELON, ETC. l6l 

side, and devour all parts except the veins and late in the 
season sometimes eat the rind of the fruit. The beetle hiber- 
nates under convenient shelter and appears abroad in May or 
June according to season and locality. A single generation 
has been observed. 

Remedies. — Remedial measures adopted for other cucurbit 
pests will effect the destruction of this ladybird. Its habit of 
feeding exposed on the leaves renders it vulnerable to poison- 
ous applications, and of these the arsenites, dry or in solution, 
are best. Hand-picking the beetles and egg masses is the only 
measure necessary under usual circumstances. 




Fig. 107.— Work of squash ladybird on a squash leaf. Natural size 
(Author's illustration, U S Dept. Agr.) 

The Squash Bug (Anasa tristis DeG.). — Of all insects which 
infest squash and pumpkin the squash bug is the best known. 
It is also called "stink-bug" from its disagreeable odor, and 
black or gray squash bug to distinguish it from the so-called 
"striped bug." In some seasons as, for example, in 1901 and 
1902, it even vies with the latter in point of destructiveness. 

The adult bug, shown twice natural size in figure 108, a, is 
nearly three-fourths of an inch long, dirty blackish brown above 
and mottled yellowish beneath. It is more or less harmful 
during its entire active existence, from the time it leaves the 
egg till its demise. When numbers attack a plant together it 



1 62 



INSECTS INJURIOUS TO VEGETABLES 



is soon exhausted, the tips and leaves wilt and its death fol- 
lows. It is not alone the extraction of the juices that destroys 
a plant; whenever the bug "stings" a leaf-stalk, it injects a 
liquid, which has a poisonous effect, causing the death of the 
cell tissue about the puncture. It attacks also the leaves and 
occasionally the fruit, and acts as a transmitter of the "wilt." 




d e 

Fig. 108.— Squash bug. a, Adult; b, egg mass; c, d, e, nymphal stages. Enlarged 
(Author's illustration, U.S. Dept. Agr.) 



On young plants a few punctures are sometimes sufficient 
to cause death. 

The common squash bug is known throughout practically 
the entire United States, being particularly abundant east of 
the Rocky Mountains, where it ranges from Maine to the 
Gulf States and westward to California. 

Injury may begin soon after the sprouting of the plants, or 
after they have made considerable growth, and may continue 
until their death or the departure of the bugs for hibernation. 
Plants are first attacked by the hibernated bugs. Soon after 
their appearance, which varies according to temperature and 
locality from early spring in the South to late in June farther 



INSECTS INJURIOUS TO CUCUMBER, MELON, ETC. 163 

north, the insects deposit their eggs, attaching them by an ad- 
hesive secretion to the leaves in masses of three or four to 
forty or more. The eggs are metallic brown or bronze and 
flattened on three sides. They are laid usually on the under 
side of a leaf, but not infrequently on the upper side, in more 
or less regular rows (fig. 108, b). They hatch in from eight 
to thirteen days into small, green and black creatures, which 
resemble somewhat the mature insects, having proportionately 
longer legs and antennae. In this period of its existence, the 
first nymph stage (fig. 108, c), the insect lives in colonies, at 




Fig. \09. —Trkhopoda pennipes. Tachina fly parasite. Three times natural size 
(Author's illustration, U- S. Dept. Agr.) 

first remaining close together upon the leaf near where the 
eggs were laid, but later congregating about the bases of leaf- 
stalks or hiding, together with individuals of the more ad- 
vanced stages, under clods or rubbish or in any convenient 
retreat, and coming forth toward dusk in search of food. The 
nymphs cast their skins five times before reaching the mature 
condition, increasing their growth with each molt. In its last 
stage the squash bug continues to feed, but with the disappear- 
ance of its food supply, caused by the dying or clearing away of 
the crop on which it has fed, it seeks shelter in any convenient 
rubbish, under boards or stones, dead vegetation, or under 



164 INSECTS INJURIOUS TO VEGETABLES 

bark, or in cracks of barns, and here passes the winter. Hiber- 
nation in the District of Columbia begins sometime in Sep- 
tember. 

This bug is often parasitized by a tachina fly which assists 
in holding down its numbers. It is Trichopoda pennipes, shown 
in figure 109, 

Methods of Control. — This insect is unusually resistant to 
insecticides. A wash strong enough to kill the mature insect 
will destroy the vines. This renders it necessary to proceed 
by hand and cultural methods. 

A lookout for the bugs should be kept early in the season 
and these as well as the eggs should be picked off or cut 
away and destroyed. The eggs are readily seen, and the 
grower should make a practice at the beginning of each sea- 
son of going over the vines every few days. Such young as 
hatch in spite of these precautions may be killed by kerosene 
emulsion if applied at their first appearance. 

The bugs may be trapped by placing about the garden boards, 
shingles, or similar material, which will attract them for shelter. 
Here they should be destroyed every morning or so during the 
early season. Protection to cucurbits other than squash, and 
perhaps pumpkin, can be facilitated by growing these plants 
with others to serve as trap crops. Attack will thus be cen- 
tered on a few plants where the insects can be the more 
readily controlled. 

A number of the remedies in use against the striped Cucumber 
beetle and other insect enemies of cucurbits will assist in the 
control of this species. Among these are the protection of 
young plants with coverings, the use of repellents, planting an 
excess of seed to distribute attack, stimulating the plant by 
manures or other proper fertilizer, and lastly, clean cultural 
practice. If the vines as soon as the crop is harvested are 
gathered and burned, many bugs will be destroyed and the 
number reduced for the ensuing year. 



INSECTS INJURIOUS TO CUCUMBER, MELON, ETC. 165 

The Melon Aphis (Aphis gossypii Glov.). — The melon aphis 
or "louse" may serve as typical of the plant-lice. It is in some 
seasons one of the most important enemies of melons and some 
other crops, and is injurious like other aphides by piercing 
the plants affected with its beak and thus sapping their vitality. 
It occurs from early spring to late in autumn on cucurbits of 
all kinds, many other crops and weeds of great variety and 
in its seasons of abundance, notably following springs that 
are cool and rainy, it frequently does very serious damage, 
causing the leaves attacked to curl, shrivel and lose color, inter- 
fering with the ultimate development of the fruit, if not kill- 
ing the plants outright. 

The melon aphis is variable dark green in color and of 
sluggish habit. 1 The principal stages are illustrated in 
figure 47. Winter eggs have been found on strawberry and 
purslane. This species is of unknown but perhaps tropical 
origin, since it shows a decided preference for, and has done 
most injury to, plants of a tropical nature, such as cucurbits, 
cotton and orange. 

METHODS OF CONTROL 

The severe losses occasioned by this insect in seasons when 
it multiplies in unusual numbers could be largely mitigated 
and, in small areas, almost entirely prevented if the employ- 
ment of methods of destruction were begun upon its first ap- 
pearance. First of all, it is necessary to familiarize oneself with 
the insect and the condition of the plants by which its pres- 
ence is manifest that measures of control may be instituted 
before it is too late. In ordinary seasons it is controlled by 
natural elements and insect enemies alone, and when the 
weather is unfavorable to the development of the latter the 
grower should be on the alert. 

1 The only other cucurbit louse with which it is apt to be confused is the 
squash aphis (Nectar ophora cucurbitce Middleton), a much larger species and 
more uniformly paler green in color. 



i66 



INSECTS INJURIOUS TO VEGETABLES 




Fig. 110.— Cantaloupe leaves showing curling caused by melon aphis; aphides on lower 
surface. Slightly reduced. (Author's illustration, U- S. Dept. Agr.) 



INSECTS INJURIOUS TO CUCUMBER, MELON, ETC. 167 

Bisulphid of carbon. — In small fields it is customary to cover 
hills of melons as soon as the insects - make their appearance 
with a tub or similar receptacle, and evaporate beneath this 
bisulphid of carbon at the rate of a drachm to a cubic foot or 
less of space. A tablespoonful serves for ordinary tubs. This 
does not injure the plant, and if the tub fits tightly to the 
ground so as to retain the vapor of the bisulphid, the "lic(; ; ' will 
all be killed. Large growers watch vines carefully, removing 
and destroying affected plants as soon as noticed to prevent 
spreading the trouble. 

Kerosene emulsion and soap solutions. — The melon aphis 
could be more readily dealt with if it did not feed on the 
under surface of leaves, and if vines like melons did not 
grow so closely together as to interlace that spraying by 
ordinary means is practically impossible. Under-spraying is a 
necessity, and the sprayer used should be fitted with an up- 
turned nozzle to secure this effect. 

Soap solutions, such as whale-oil, fish-oil and potash soap, 
are not so useful. 

Clean farming with fall plowing should always be followed, 
as it is a most valuable measure of prevention of attack by 
aphides and other insects that are present. As soon as the crop 
is off remnants should be gathered and burned, and all weeds 
kept down until the fields are again planted, since, as has been 
shown, common weeds of the field and garden serve as alter- 
nate food plants, and are selected as hibernating quarters by the 
"lice." 

Pyrethrum applied to the underside of the leaves with a 
powder bellows is effective, but can not be used with profit on 
large fields or on plants like squash with large leaves. 

Remedies that have been indicated as of service in the con- 
trol of the melon aphis operate against many other insects 
which are usually present at the same time. Thus the kero- 
sene and soap solutions kill small squash bugs and act as 



i68 



INSECTS INJURIOUS TO VEGETABLES 



deterrents of other insects, bisulphid of carbon destroys other 
aphides and small bugs, as does also pyrethrum. 1 

The Squash-vine Borer (Melittia satyriniformis Hbn.). — A 
most troublesome enemy of squash, pumpkin and other cucur- 
bits is the squash-vine borer. In many localities it surpasses 
all other squash insects in point of injuriousness. Damage is 
due to the white grub-like larvae boring through the stems, 
causing them to rot at the affected points and become severed 
from the vine. The presence of the borer in the stem is not 
apparent at the commencement of the attack, but soon becomes 
manifest through the presence of the yellowish powdery excre- 




Fig. 1 1 1.— Squash -vine borer, a, Male moth; £, female, with wings folded in natural 
position when at rest; c, eggs shown on bit of squash stem; d, full-grown larva, in situ 
in vine; e, pupa; /, pupal cell. All one-third larger than natural size. (Author's illus- 
tration, U. S. Dept. Agr.) 

ment which it forces from its burrow in the stem and which 
accumulates on the ground beneath, as well as by the sudden 
wilting and dying down of the leaves. From one to upwards 
of 145 individuals have been reported taken from a single plant. 
The larvae work with great rapidity and in a short time in- 

*A detailed account of the melon aphis, Circ. 80, Bu. Entom., U. S. Dept. 
Agr., should be consulted for a full consideration of remedies. 



INSECTS INJURIOUS TO CUCUMBER, MELON, ETC, 169 

jure a plant so that no fruit will mature. Injury is most notice- 
able near the bases of the stems, where in course of time the 
vine becomes severed from the roots. 

The parent insect (fig. in, a) is a beautiful clear-winged 
moth. The fore-wings are lustrous olive-brown, with metallic 
green reflections, and expand about an inch and a fourth. The 




Fig. 1 12.— Squash-vine borer, a, Egg- as seen from above; b, same from the side 
showing- sculpture; c, sculpture of egg greatly enlarged; d, newly-hatched larva; e, 
half-grown larva; /, head of same from side; g, head of mature larva from above, a, b 
and d, Much enlarged; e, fandg, less enlarged. (Author's illustration, U. S. Dept. Agr.) 



abdomen is marked with orange or red, black and bronze, and 
the hind-legs are fringed with long hairs. 

The larva is soft, whitish and grub-like. Mature larvae 
measure about an inch. In the District of Columbia full-grown 
larvae occur as early as the middle of July and as late as the 
second week of November. After attaining maturity the 
larvae enter the earth to the depth of one or two inches and 
form cocoons (fig. in, /) constructed of silk and coated ex- 
ternally with fine particles of earth. Observations indicate 
that this species is practically single-brooded northward; that 
there is a tendency to two broods in New Jersey; that in the 
District of Columbia the species is partially double-brooded, 
and that in the Gulf States it is fully two-brooded. 



170 INSECTS INJURIOUS TO VEGETABLES 

PREVENTIVE AND REMEDIAL MEASURES 

This borer is exceptionally difficult of control, as ordinary 
insecticides are of no value after the insect has entered the 
vines, and repellents are also practically useless. We are, there- 
fore, dependent upon cultural methods for relief. Knowing 
that the insect passes the winter in the fields which it has 
ravaged, it should be superfluous to caution growers not to 
plant squashes in the same ground in successive years. 

Early squashes as traps. — Good results are obtained by plant- 
ing as early as possible a few summer squashes, such as crook- 
neck and early cymblin, before, and between rows of, the main 
crop of late varieties. The summer squashes attract the in- 
sects in numbers, leaving a smaller number to deal with on 
the main crop. As soon as the early crop is gathered, or 
earlier if the ground is needed for the main crop, the vines are 
raked up and burned to destroy all eggs and larvae which they 
may harbor, and the same treatment is followed after gathering 
the late varieties. 

Fall harrozving and spring ploning. — This species can be 
greatly reduced by lightly harrowing the surface of infested 
squash fields in the fall so as to bring the cocoons to the 
surface, where they will be exposed to the elements, and then 
plowing in the spring to a uniform depth of at least six inches 
so that the adults will not be able to issue. 

Cutting out the borers, although laborious, is about the only 
method open for employment after they have entered the vines. 
It is best to cut longitudinally, so as not to sever the vine 
from the root stalk. The location of the borer in the vine can 
be detected by the accumulation of its yellow excrement at 
the point where it is working. 

Other methods. — When vines have attained some length parts 
of them should be covered with earth so that secondary roots 
will be sent out in case the main root is injured. Keeping plants 



INSECTS INJURIOUS TO CUCUMBER, MELON, ETC. 171 

in good condition, free from disease and other insects, and well 
nourished, with the assistance of manure or other fertilizer if 
necessary, will also aid them to withstand attack. If the 
grower would make certain of securing a good crop in localities 
where this and other enemies of the squash occur in their most 
destructive abundance, it will be necessary for protection against 
this borer to observe most of the precautions specified and, if 
possible, secure the cooperation of his neighbors. 

The Pickle Worm (Diaphania nitidalis Cram.). — In the Gulf 
States and occasionally farther northward two caterpillars are 
quite injurious to the fruit of melons and other cucurbits. The 
term "melon worm" is applied to both, as also to the squash 
borer, since all have the habit of boring into melons ; the last- 
mentioned, however, is a vine-borer, while the other two, known 
respectively as the pickle worm and melon caterpillar, feed in 
their earlier stages in the buds or leaves, and in their later 
stages in the fruits, which they frequently destroy. They are 
about equally destructive and work usually by boring directly 
into the interior, but sometimes eat cavities in the rind. 

Injury by the pickle worm is seldom noticed until it enters 
the fruit. 

The moth (fig. 113, e) is a beautiful creature, quite distinct 
from any other common species. The upper surface is brown 
with purplish iridescence. Near the middle of the fore-wings 
is a somewhat irregular yellowish semitransparent spot, and 
the inner half or a little more of the lower wings is of the 
same color. The wing expanse varies from an inch to nearly 
one and a half inches. Larvae (a, b, c) vary from yellowish 
to dull brownish green, with a dorsal row of shining round 
spaces of the same color. 

The pickle worm is indigenous to America and is probably of 
tropical origin. It occurs from South America to New York, 
Michigan and Illinois. It is injurious every year in the Gulf 
States, instances of damage farther north being only periodical. 



1J2 



INSECTS INJURIOUS TO VEGETABLES 



Injury appears to be practically due to the later-appearing gen- 
erations, and more especially to muskmelons raised for north- 
ern markets. In September, 1897, fields of cymblins cultivated 
in Maryland, Virginia and the District of Columbia were 
badly damaged or totally destroyed by the pickle worm, but 
in the after years the insect has almost entirely disappeared. 
The life history and habits of this species have been studied 




Fig. 1 13.— Pickle worm, c, Larva; b, head and first three segments of larva; c, segment 
from side; d, pickle showing injury; e, moth; /, cocoon, c, d, e, f, Slightly enlarged; 
b, c, more enlarged. (After Riley.) 



by Prof. A. L. Quaintance, in Georgia. Larvae are first noticed 
there about the middle of June. Eggs are deposited on the 
flowers, buds, or tender portions of a plant. The larvae first 
eat out cavities in the leaves or stems, the angle between a leaf 
and stem being a favorite place of entrance. Frequently they 
enter flower buds, and have been found by the writer destroying 
many prospective cymblins in this manner. With the second 
stage, at least southward, the larvae feed on the young fruit, 
and as they mature they pass from plant to plant and thus 
injure for sale much of the fruit affected. They void large 



INSECTS INJURIOUS TO CUCUMBER, MELON, ETC. 1 73 

quantities of soft excrement and when several larvae have bored 
into a fruit it becomes a most disgusting object, quite different 
from the beautiful moths as they flit about the garden. The 
length of the life cycle in the South in midsummer is between 
24 and 27 days and three generations seem to have been 
definitely recognized there. When the larvae have finished 
feeding they crawl out from the infested fruit and transform to 
pupae within the fold of a leaf or under any sort of debris on 
the ground. 

Methods of Control. — The methods that have been ad- 
vised as most valuable against the striped cucumber beetle and 
other species, more particularly clean farming, fall plowing 
and rotation of crops, are useful, but the pickle worm has 
never been successfully combated. The writer suggests the 
combined use of arsenate of lead and Paris green, spraying with 
the former, at the rate of one pound to from 15 to 25 gallons 
of water, beginning at about the time that the buds commence 
to form, and making a second application a week or two later, 
according to how well the arsenate remains on the foliage. A 
third spraying may be made if necessary, following with a final 
:pray of Paris green (1 pound to 130 gallons water) within 
about a week of the time of the ripening of the fruit. As the 
arsenate is very adhesive, its use is not advised for the final 
spraying. The Paris green which is substituted at this stage 
is perfectly harmless, as it readily washes off if, indeed, any 
will remain by the time the fruit is placed on sale. This 
treatment is designed to kill the "worms" before they enter the 
fruit, since they cannot be reached after they have obtained 
entrance. The "worms" are poisoned while feeding on the 
buds, leaves and other parts, as well as on the rind of the 
fruit. 

The Melon Caterpillar (Diaphania hyalinata Linn.). — This 
species and the preceding resemble each other in many partic- 
ulars and are especially alike in their larval stages, but there 



174 INSECTS INJURIOUS TO VEGETABLES 

is this difference, important to the grower, that the first genera- 
tion of the melon caterpillar usually attacks the foliage, partic- 
ularly of muskmelon, to which it, as well as the preceding, is 
most destructive. By reason of this habit we can control it, in 




Fig. 1 14.— Melon caterpillar. Moths, larva and pupa in case. Natural size 
(From Comstock) 

a measure at least, with stomach poisons, which is impossible 
with the pickle worm, since the latter lives internally through- 
out its later larval stages. 

The parent insect has the wings pearly white, with a strong 
iridescence, and bordered with brown (fig. 114). The cater- 
pillar when full grown is a trifle smaller than the pickle worm, 
measuring about eight-tenths of an inch. It is pale, greenish 
yellow, with black mouth-parts. It is southern in distribution, 



INSECTS INJURIOUS TO CUCUMBER, MELON, ETC. 1 75 

occurring abundantly in the Gulf States. The "worms" of 
these two species are frequently confounded because of their 
similar appearance. Both feed in the same fields and their life 
habits exhibit little variation. 

Remedies mentioned for the pickle worm are applicable, as 
the melon caterpillar can be killed readily by an arsenical spray. 

Miscellaneous Pests. — The onion thrips, considered on 
pages 89 and 90, the wheat thrips (page 90) and the red spider 
(page 91) are all important enemies of 
cucumbers grown under glass, as is also 
the greenhouse white fly (Aleyrodes 
vaporariorum Westw., fig. 114^). In- 
deed in the case of the last mentioned 
pest it would be impossible to grow this 
crop in forcing houses without the em- 
ployment of remedial measures. 

This pest can be held in control by 
vaporization or fumigation with tobacco 
or nicotine extracts, or by spraying with 
kerosene emulsion or the so-called whale- 
oil (fish-oil) soap. Care is necessary in 
using the extracts that the smudge does Fig-, wax— Greenhouse 
not become too dense and injure the ^tlL^t^ 
plants. Before applying this remedy on nified. (After Morrill.) 
a large scale a preliminary trial should be made following the 
directions on the packages, and reducing the amount if any ill 
results follow. Hydrocyanic acid gas properly used is an ex- 
cellent remedy. 1 

1 See Circ. 57, Bu. Entom.. U. S. Dept. Agr., and Fumigation Methods, by 
Prof. W. G. Johnson, published by Orange Judd Company, New York. 





CHAPTER XI 

INSECTS INJURIOUS TO CELERY, PARSNIPS 
AND RELATED PLANTS 

A considerable number of insects attack celery, but few 
are restricted to it as a food, and fewer yet do noticeable 
damage. A large proportion of the insects which live on it also 
attack carrot, parsnip, and parsley, preferring one or the other 
of these three plants. For convenience, however, we may con- 
sider the insect enemies of celery separately. 

INSECTS INJURIOUS TO CELERY 

What is true in this country is equally true in Europe, and 
there is little danger of the introduction of important pests from 
abroad. With the increased cultivation of this crop insects which 
now attack it may increase in injuriousness, but there is no 
immediate prospect of serious losses accruing from insect at- 
tack. It is seldom that beds of celery are entirely free from 
the celery caterpillar; the same may be said of the zebra cater- 
pillar. The tarnished plant-bug is one of the worst enemies 
with which the celery grower has to contend, but its having 
many host plants usually distributes attack except in unusual 
seasons. Celery generally escapes the ravages of cutworms 
owing to its late planting and still later replanting, and neither 
white grubs nor wireworms deter its growth as far as observa- 
tions go, presumably because of its powerful root and root 
stalk. The leaves are attacked by leaf-rollers and leaf-tyers 
and one of these, the celery leaf-tyer, is of considerable im- 
portance. 

The Carrot Rust Fly (Psila rosce Fab.). — This pest has been 
injurious to carrots in Canada since 1885 and made its ap- 
176 . 



INSECTS INJURIOUS TO CELERY, PARSNIPS, ETC. 



177 



pearance in 1901 in New York in celery fields. In attack on 
celery the leaves of young plants early in spring turn reddish, 
and the roots are blotched with rusty patches, particularly 
toward their tips. Roots of carrot when stored for winter, al- 
though not manifesting any degree of injury on the outer 
surface, are at times perforated in all directions by dirty brown- 




Fig. 115.— Carrot rust fly. $ . Male fly; $ , female fly; a, antenna of male; b, full- 
grown larva, lateral view; c, spiracles of same; d- anal extremity; e, puparium; /. young 
larva; g, anal segment from side. Flies, young and mature larva, and puparium, eight 
times natural size; other portions more enlarged. (Author's illustration, U. S- Dept. 
Agr.) 



ish burrows, from which these whitish yellow maggots may be 
found projecting. When celery is infested the larvae seem to 
begin eating into the thick part of the root when the plant is 
about half grown, stunting it so as to make it worthless for 
market. 

This species is quite minute, the parent fly measuring only 
about one-sixth of an inch in length, with a wing expanse of 
a little more than three-tenths of an inch. The body is dark 
green and is rather sparsely clothed with yellow hairs. The 
head and legs are pale yellow, and the eyes black. The two 
sexes are shown at $ and $, figure 115. According to Curtis, 
when the imago issues from the puparium an oval lid on this 
portion lifts up, permitting the fly to crawl out. The posteiior 
extremity ends in two minute dark tubercles. 

The carrot rust fly is a pest in Europe, whence it has been 
introduced in this country. It is a northern species and is 



I78 INSECTS INJURIOUS TO VEGETABLES 

permanently established in New Brunswick, Ontario and Que- 
bec, Canada, besides occuring in New York and New Hamp- 
shire. 

The life history of the carrot fly has not been entirely worked 
out. In the United States it will probably be found to pass 
the winter usually as a puparium, but as larvae work also on 
carrots in store, the flies develop in winter, hence we have 
great irregularity in development, making generalization im- 
possible until observations are made in the field. 

The insect develops rather early in the season and both 
flies and maggots are found throughout the warmer months, 
but the latter desert the roots for pupation in the earth, the 
last generation probably descending much deeper than the 
earlier ones. Curtis states that the summer generations develop 
in three or four weeks. There are at least two, and probably 
more, generations annually. Miss Ormerod has observed that 
the female fly goes down into the ground where she can find 
a crack or other opening about the roots of the plant affected. 
Here she lays her eggs, and the maggots, when hatched, work 
their way into the root; when this is quite small they often 
destroy the lower portion. 

METHODS OF CONTROL 

The carrot rust fly is difficult to reach with insecticides. Our 
principal dependence is based upon methods of tillage which 
will avert attack. 

Kerosene emulsion in the proportion of one part to ten of 
water sprayed upon the carrots along the rows, or sand, or 
ashes, with which kerosene is mixed at the rate of half a pint 
to three gallons, sprinkled along the rows, have given good 
results. These substances deter the fly from laying her eggs. 

Late sowing and rotation of crops are excellent remedies, 
as is also the planting of new beds as far as possible from 
land infested the previous season. 



INSECTS INJURIOUS TO CELERY, PARSNIPS, ETC. 179 

Destruction of stored carrots. — Where carrots are stored for 
winter use in earth they should be treated to destroy the larvae 
or puparia. This may be accomplished by burying the earth 
deeply; by spreading it in thin layers where it will be exposed 
to the elements; by throwing it into pools where it will be 
frozen; or by exposing it to heat or steam in any convenient 
manner. 

Treatment of celery beds. — As this insect also infests celery, 
that crop should not follow carrots (nor carrots celery) in 
rotation. Clean farming should be practiced, which includes the 
destruction of remnants after the crop has been harvested. 

After harvest, it would be a good plan to give celery fields 
a raking or cultivating of sufficient depth to expose the larvae 
or puparia to frost; early the following spring, before the flies 
issue, if the earth be plowed deeply, it will have the effect of 
destroying such insects as have not been killed by frost and 
survive cultivating and raking. 

The Celery Caterpillar (Papilio polygenes Fab.). — Because of 
its large size and brilliant colors, both as larva and adult, this 
is one of the best known of the enemies of celery and allied 
plants. The caterpillar is green, or yellowish, and ringed with 
black and spotted with yellow. It attains a length of two inches. 
The parent insect is known as the black swallow-tail. It is 
velvet black, relieved by yellow bands in the male. The hind- 
wings are ornamented on the interior margin by eye-like mark- 
ings like those of the peacock and the wings terminate in 
the tails from which it derives its common name. The female 
is somewhat faded black and of more sombre appearance than 
her mate. The wing expanse is about three inches. The 
chrysalis is dull gray, mottled with dull brown. It measures a 
little less than one and one-fourth inches. The celery cater- 
pillar is one of the most interesting insects that attack garden 
plants. It appears to be limited to no special life zone, occur- 
ring throughout Canada and every State and Territory in the 



l8o INSECTS INJURIOUS TO VEGETABLES 

Union, southward through Central America and the West Indies 
to Venezuela. The young larvae are utterly dissimilar to the 
mature ones, and five distinct stages have been noted. 

This insect affects practically all umbelliferous crops, celery, 
carrot, parsley, caraway, fennel, parsnip, dill, and related wild 
plants. It does not appear to attack, except in extreme cases, 
any plant outside of this botanical family. 

Remedies. — The conspicuous coloration of the celery cater- 
pillars renders them an "easy mark" as they are readily found 
and can be crushed under foot, and no other remedies are 
necessary if the work of destruction is begun before the 
plants are injured. The killing off of the first generation will 
serve in considerable measure to destroy the insects for the 
second brood, if this work be done over a considerable area. 
The butterfly, however, is strong of flight, and cooperation must 
be had to keep the insect in check when it becomes destructive. 

The Celery Leaf-tyer (Phlyctamia ferrugalis Hbn.) 1 .— This 
little insect, known also as the greenhouse leaf-tyer, first came 
to notice as a pest in 1888. On celery it feeds by preference 
on terminal leaves, and sometimes burrows into the stems. On 
one occasion in the District of Columbia it was so destructive 
that one grower had determined to abandon celery culture on 
this account. Next year, however, the insect was less trouble- 
some; and this was fortunate, for if it were not periodical it 
might be a very bad pest indeed. In the field this leaf-tyer 
attacks besides celery cabbage, beets, tobacco, lettuce, cauli- 
flower, parsley, cucumber, sweet pea and strawberry. It causes 
great injury to many greenhouse plants — violet, rose, chrysan- 
themum, carnation, ivy, heliotrope, and others. 

The moth is a pale reddish-brown, expanding about three-fourths 
of an inch. The fore-wings are pale clay brown, suffused 
with reddish or ochreous brown, ornamented with black lines 
(fig. 116, a, b). The hind-wings are gray, with darker margins. 

1 For a detailed account see Bui. 27, Bu. Entom., U. S. Dept. Agr. 



INSECTS INJURIOUS TO CELERY, PARSNIPS, ETC. l8l 

This moth resembles that of the garden webworm (page 61). 
The larva is green or greenish yellow, somewhat translucent, 
with whitish head, marked with purplish dots (fig. 116, e, d, f). 

This is an introduced species, and obviously of tropical origin. 
Owing to its adaptability to indoor habits it is likely to be 
found anywhere. 

The leaf-tyers work usually on the under surfaces of leaves, 
or on such as are shaded by other leaves. When young they 
eat out small holes on the under surfaces, leaving the upper 




Fig. 116.— Celery leaf-tyer. a, Moth; b, same in natural position at rest; c, egg mass; 
d, larva from above; e, same from side; /, head of same; g, pupa case; h, chrysalis. 
a, b, d, e, g, h, One-half larger than natural size; c, twice natural size; /, more enlarged 
(original). 



epidermis untouched; but as they increase in growth the 
leaves are skeletonized and sometimes entirely devoured. Larvae 
work chiefly at night and rest by day in the same locations. 
They prepare for transformation to pupae by spinning up be- 
tween two leaves, or by rolling up a case at the edge of a leaf. 
(See fig. 116, g). Owing to the somewhat secluded manner 
of life of the larva, attack is not noticeable until considerable 
injury is done; but its presence can be readily ascertained by 
striking the plants lightly, when the moths start up, fly a short 
distance, then alight, and disappear under a leaf. In mid- 
summer the entire life cycle, according to the writer's observa- 



1 82 



INSECTS INJURIOUS TO VEGETABLES 



tions, may be passed in five weeks, but the outdoor spring and 
fall generations require a longer period. There are at least 
two, and frequently three, generations produced in the open; 
and in a warm equable indoor temperature there is a possibility 
of four and perhaps five. 

Remedies. — In greenhouses this leaf-tyer is controlled by 
trimming away and destroying infested leaves as often as they 
are detected. The moths are killed in great numbers by placing 
lights over vessels of water on which a thin scum of kerosene 
floats. These remedies are less valuable in the field, but Paris 
green and other arsenical sprays, if applied at the outset of 




Fig. 1 1 7.— Celery looper. Male moth at left, larva at right. Somewhat enlarged 
(Author's illustration, U. S. Dept. Agr.) 

attack, will destroy the larvae, though less effective after they 
have become concealed in their tied-up leaves and in the growth 
of leaves about them. Spraying should be thorough, and an 
underspray is desirable. 

The Celery Looper (Plusia simplex Guen.}. — This species is 
the commonest of its kind in Illinois, and is rather generally 
distributed in the United States east of the Rocky Mountains, 
from Canada to New Mexico. It is described by Messrs. 
Forbes & Hart as a very destructive celery insect, and occurs 
also on sugar beet and lettuce. 

The moth (fig. 117) has a greater wing expanse than the 
cabbage looper, measuring nearly two inches, has different 
coloration, and differently shaped upper-wings. The border of 
the fore-wings is not scalloped, the color is somewhat purplish 



INSECTS INJURIOUS TO CELERY, PARSNIPS, ETC. 183 

brown, the darker shades velvety brown. The larva is similar 
to the cabbage looper and similar remedies are applicable. 

The Little Negro Bug {Corimelcena pulicaria Germ.). — This 
minute black bug sometimes does considerable damage to 
celery, as happened in 1893, when attack was quite general 
throughout the celery-growing portions of Michigan. The 
insects collect in clusters around the nodes where the three 
top leaflets meet. Here they suck the sap until the leaflets 
wilt and droop, after which they go to the joint below and 
repeat the operation till the leaf is drained of sap. 

The mature negro bug measures only about an eighth of an 
inch, and is glossy black, the scutellum occupying over half of 
the upper surface and being surrounded by a white margin. This 
insect is common and well distributed. It prefers old celery 
when about ready for blanching and plants are retarded in 
growth from two to three weeks, recovering with large numbers 
of small curling, gnarly stalks of little or no market value. 
In such cases the crop is practically an entire loss. This 
species is a general feeder attacking numerous garden plants, 
among which are strawberry and blackberry, and it is due in 
part to this insect that these berries sometimes have such a 
disgustingly sour taste, and "buggy" odor, particularly when 
picked in the field. 

Remedies. — Carbolic or kerosene emulsion are useful both 
as destroyers and repellents. In experiments conducted by Mr. 
G. C. Davis, the bugs were readily killed with hot water at a 
temperature of 155 F., acid the celery plants were found to 
endure a stream heated to 175 . This remedy is most effective 
when the insects first appear and when applied on the plants 
where they are most numerous. It necessitates the use of a 
thermometer that the temperature may not go above 175 . 
Celery should not be planted in the vicinity of weedy fields, 
especially those containing umbellifers, as these harbor the 
insects sometimes in enormous numbers. 



184 INSECTS INJURIOUS TO VEGETABLES 

INSECTS INJURIOUS TO CARROTS, PARSNIPS 
AND PARSLEY 

In this category we include parsley although it does not 
seem to have any insect enemies of its own. These plants 
belong to the same family (Umbelliferae) as celery, and as 
stated in a preceding page most of the insects enumerated as 
affecting that plant are liable to attack these also, but both 
parsnip and carrot have particular species that infest them, 




Fig. 118.— Parsnip leaf-miner, o, Fly; b, larva; c. cephalic extremity of larva; d, anal 
extremity; e, /, spiracles- All enlarged. (After Coquillett, U. S. Dept. Agr.) 

because they are planted for their roots and not for their 
delicate stalks, as in the case of celery, which renders the por- 
tions above ground more rank and those below ground more 
tender, while each plant (parsnip and carrot) has a flavor 
peculiar to itself. Thus it happens that the leaves of parsnip are 
more affected by the parsnip leaf-miner, while the roots of 
carrot are preferred by the carrot beetle and carrot rust fly. 
The Parsnip Leaf -miner (Acidia fratria Loew.). — The 
economic history of this species begins with 1891, when parsnip 
leaves in Missouri were quite extensively mined by its larva. 



INSECTS INJURIOUS TO CELERY, PARSNIPS, ETC. 185 

The adults issued June 23. The insect which produces this 
maggot is shown at figure 118, a. It belongs to the same family 
as the apple maggot or railroad worm, and it will be seen that 
it is a two-winged fly, with rather prettily marked wings. It is 
pale dull- yellow, and the wings are marked with the same color. 
The legs are still paler, and the eyes are brown. The head and 
thorax above bear long, stiff bristles. This fly measures about 
three-sixteenths of an inch in length, and has a wing expanse 
at least double that. It ranges from the Atlantic seaboard 
westward to Missouri and probably farther. Little is known 
of its life history, but it will probably be found to affect other 
umbelliferous crop plants and weeds. 

Remedies advised against the radish leaf-miner (page 154) 
are applicable. 

The Carrot Beetle {Li gyrus gibbosus DeG.). — This beetle is 
the worst insect enemy to carrot and parsnip in this country. 
It is a native species and of common oc- 
currence along the Atlantic Coast from 
Long Island to the Gulf and Pacific States 
and at many points inland. It injures be- 
sides the plants specified various root 
crops and some other plants. 

The beetle might be mistaken for a May 
beetle, but the wingcovers are strongly 
sculptured and coarsely punctate, char- 
acters' which are wanting in true May p . g ® 9 ._ Carr0t f eetle . 
beetles (Lachnosterna). The beetle (fig. About twice natural size. 
119) is of robust form, measuring between g^^^*"' ""* 
one-half and five-eighths of an inch in 

length, with short legs. The color varies from reddish brown 
to nearly black on the dorsal surface. Larval injury has been 
noted, but there is little doubt that the grubs feed also on humus, 
manure and decomposing roots and tap roots of herbaceous 
plants. Larvae have been observed to feed on earth where there 




1 86 INSECTS INJURIOUS TO VEGETABLES 

was no opportunity for plant attack. Most cases of injury are 
due to the operations of the beetles, and damage is more pro- 
nounced on young plants, older growth appearing in some cases 
exempt from attack, owing to its more woody texture. Injury 
may be accomplished both by hibernated individuals in the 
spring from April to June, according to locality, and by recently 
transformed specimens in late summer and autumn. 

The species is with little doubt single-brooded. Pupation 
takes place in an oval cavity in the earth, and hibernation, 
without much doubt, occurs in the adult condition. The 
favorite food of the beetle is evidently carrot, and after this 
corn, parsnip and celery are chosen. Sweet and Irish potato 
are subject to much damage, as are also sunflower, dahlia, sugar- 
beet and sometimes cotton. The beetles usually feed beneath 
the surface; corn is cut just above the roots, and root crops are 
punctured with holes. Sometimes a crop appears in good condi- 
tion, judging from the tops alone, but when the plants are 
pulled injury becomes manifest. Entire plantings have been 
destroyed by the beetles, and the roots of tubers rendered un- 
marketable on account of their ravages. They gnaw into the 
roots of celery, dwarfing and killing the plants, and eat the 
bark from the root. They sometimes imbed themselves in tap 
roots and may penetrate the earth to a depth of seven inches. 
As many as fifty beetles have been found about the roots of 
a single plant. 

Methods of Control. — When this insect is present in large 
numbers there is little, owing to its working underground, that 
can be accomplished in the line of control. The beetles are 
strongly attracted to electric lights, but it is not certain that 
they could be lured from the field after beginning to feed. It 
is reported that lime scattered through infested fields has ap- 
parently driven the beetles away. After the crop has been har- 
vested, if the insects continue in numbers in the ground, it would 



INSECTS INJURIOUS TO CELERY, PARSNIPS, ETC. 187 

be profitable to turn in hogs or chickens. Crop rotation and 
other white-grub remedies should be practiced. 

The Parsnip Webworm (Depressaria heracliana DeG.). — The 
parsnip webworm is injurious to the seed of parsnip, but for 
some reason, at least in the experience of the writer, prefers 
the wild carrot as a breeding plant. The moth is grayish buff, 
or pale ochraceous, with the fore-wings marked with fuscous 
(fig. 120, e). The larva is pale yellow, greenish or bluish gray, 
marked with black, piliferous spots, and with bluish black head 




Fig. 120.— Parsnip webworm. a, Mcfth; b. c, caterpillars: d, chrysalis; e anal segment 
of same; /. umbel of parsnip, webbed together by caterpillar, a- e. Enlarged; /, some- 
what reduced. (After Riley ) 



and thoracic plate, as figured (a, b). The species is of general 
occurrence through the northern portions of Europe and our 
Atlantic States and Canada westward to Michigan. Wild 
carrot and parsnip, which are altogether too abundant in fields 
throughout that section, yield it a sufficiency of food and in some 
years it is difficult to find these weeds that are not affected 
by the webworm. The larvae weave the flower heads (/) 
together until these are contracted into masses, with abundant 
excrement as a covering. Within the domicile thus formed the 
larvae dwell. After they have consumed the flowers and unripe 



1 88 INSECTS INJURIOUS TO VEGETABLES 

seeds and are nearly mature, they enter the stems, feed on the 
soft lining, and transform to pupae. They sometimes destroy 
newly-sown parsnip, eating the tender leaves, but in attack on 
older plants they eat the umbels or flower heads and the inte- 
rior of the stems. 

Remedies. — A thorough spraying with arsenicals will destroy 
this webworm. To prevent injury by it avoid planting parsnips 
in or near waste places which have become overrun with wild 
carrot. 

Miscellaneous Insects. — Among other insects injurious to 
celery the tarnished plant-bug is an important species. It is 
figured and described on pages 87 and 88. The cotton leaf-bug 
(Calocoris rapidus Say), a species of somewhat similar habits 
and appearance (fig. 120^), also attacks celery and is amenable 
to the same remedial treatment. 



CHAPTER XII 

INSECTS INJURIOUS TO SWEET CORN 

A greater number of species of insects have been recognized 
as attacking Indian corn than any other plant grown as a 
vegetable. Although, properly speaking, corn is a field crop, it 
is also grown for the sake of the unripe ears which are classi- 
fied as vegetables. What insects will attack field corn will 
also attack the garden variety, but for present purposes it will 
not be necessary to treat of any except the more important 
habitually garden-inhabiting species, and only a few of these 
need be considered at all in detail. Many of them are general 
feeders and have been considered in preceding paragraphs. 

The corn-feeding species of insects recognized in 1896 were 
214 in number, and of these 18 attacked the seed, 27 the root 
and lower portions of the stalk, 76 the stalk above ground, 118 
the leaf, 19 the tassel and silk, and 42 the ear. The remainder 
attacked the stored product. It is safe to say that at the present 
writing (1907) at least 350 species are on record as concerned 
in attack on corn. 

The Corn Root-aphis (Aphis maidiradicis Forbes). — Con- 
cerning this species, Dr. S. A. Forbes wrote in 1896: "No in- 
sect affecting corn is more deserving of the attention of farmers 
and entomologists at the present time than the corn root-aphis. 
It ranks as a corn pest with the chinch bug and the army worm, 
less injurious at any one time than these are locally and occa- 
sionally, but overtaking them, on the other hand, by its general 
distribution and the constancy of its attack." This root-aphis 
does its principal injury while corn is small. The dwarfing of a 
plant in patches with a yellowing or reddening of the leaves, and 

189 



190 



INSECTS INJURIOUS TO VEGETABLES 



a lack of thrift and vigor, are the outward manifestations of 
injury. Another indication is the presence of numerous small 
brown ants which attend this species and without which it 
probably could not exist. 

The corn root-aphis is bluish green, slightly whitened by a 
waxy bloom. The body is oval, and the nectaries are erect or 




Fig. 121.— Winged viviparous female of corn root-aphis; wingless egg-laying female. 
Enlarged. (After Forbes) 

project slightly backwards. Two of the different forms are 
shown in figure 121. It is found from Massachusetts to Minne- 
sota and Nebraska and as far south at least as Virginia. 

The winged forms migrate to various weeds, among which 
are smartweed, pigeon grass, mustard, pigweed and plantain. 

Economic Treatment. — Our present knowledge of this insect 
suggests several methods of attacking it. Crop rotation and 
care not to plant in or near fields of weeds which serve as 
alternate hosts; the free use of manures and other fertilizers to 
stimulate the growth of the plants; the disturbing and destruc- 
tion of the nests of the protecting ants; the destruction of all 
of the weeds which serve the aphides as food early in the 
season by plowing, and, in connection with this, late planting 
of corn. 1 Such measures of procedure may not entirely pro- 
tect the crops in all localities in all seasons. 

1 These and other remedies are considered in detail by F. M. Webster in 
Circ. 86, Bu. Entom., U. S. Dept. Agr. 



INSECTS INJURIOUS TO SWEET CORN 191 

The Southern Corn Root-worm (Diabrotica 12-punctata 01.). 
■ — The larvae of two species of leaf-beetles are among the promi- 
nent enemies to the culture of corn by destroying the roots. 
One of these, the Southern corn root-worm is common nearly 
throughout the United States, but as its name implies is most 
destructive in the South. In the case of its attack not alone 
roots, but underground stalks are injured. The other, known 
as the Western corn root-worm, is somewhat confined to the 
middle West, where it would be a very serious pest were it 
not that farmers generally in that region have adopted a sys- 
tem of rotation which greatly reduces injury. The principal 
form of its attack is in the interior of the fibrous roots, in which 
minute, more or less longitudinal, burrows are formed. 

The larva of the Southern species is also called in the South 
the "bud-worm" and "drill-worm." The beetle is commonly 
known northward as the twelve-spotted cucumber beetle be- 
cause of its frequenting the flowers of cucumber, as well as 
squash, and other cucurbits in the interior of which one can 
usually see one or more dusted with pollen, and the places where 
they have gnawed the petals, for they are mbst omnivorous in- 
sects and able to subsist on nearly any form of vegetation on 
which they happen to alight. They are, in fact, to be found in 
practically all fields of corn and in gardens everywhere. 

The beetle is yellowish green, and the wing-covers are 
marked with twelve black spots (fig. 122, a). The length is 
one-quarter of an inch or a little longer. The larvae (c) are 
slender, thread-like, delicate and soft bodied, and white or yel- 
lowish in color. 

The twelve-spotted cucumber beetle inhabits that portion of 
America lying between the Atlantic seacoast to the base of the 
Rocky Mountains, and from Canada to Mexico. It is a very 
common species and most destructive in the South, where in- 
jury is accomplished by its root-worm form as far northward 
as Maryland and Virginia. 



192 



INSECTS INJURIOUS TO VEGETABLES 



The adult is practically omnivorous, its known food ma- 
terials are legion, and include besides the pollen and flowers 
and partly matured kernels of corn, wheat and oats, the foliage 
of alfalfa, crimson clover, cotton, rye and tobacco. Of vege- 
tables it attacks all forms. It frequently injures the fruit of 
melon and other cucurbits. Larvae or pupae have been ob- 
served at the roots of corn, wheat, rye, millet, beans, rudbeckia 




Fig. 122.— Southern corn root-worm, a, Beetle; b. egg; c, larva; d, last segment of 
same; e- section of cornstalk showing holes made by larvae; /, pupa, <z, c, /, Consider- 
ably enlarged; b, d, more enlarged; e, reduced, (a-d, After Riley; e, f, redrawn, U- S. 
Dept. Agr-) 



and sedges. In fields of corn this root-worm gives origin to 
the loss of roots, injury varying according to the age of the 
corn and severity of attack,- and somewhat also upon the con- 
dition of the weather, and even of the soil. Injury is mani- 
fested in various ways: from the death of a plant to re- 
tardation of growth, or to what is termed "spindling," or a 
yellowish, unhealthy look. In plants six inches or less in 
height the perforations of the stalk (fig. 122, c) are character- 



INSECTS INJURIOUS TO SWEET CORN 193 

istic, and usually show just below the surface. This is ac- 
complished by more or less withering of the plant, which is 
frequently killed outright by the destruction of the central 
tuft of growing leaves. Frequently plants are destroyed al- 
most as soon as sprouted. Should the plants survive ordinary 
attack they are apt to fail to produce mature ears. If plants 
which are suspected of harboring this species are pulled up, the 
root-worms can be dislodged, and it is not difficult to distinguish 
them from other forms of insects found in the same locations, 
with the exception of the western corn root-worm, which, 
however, seldom occurs in the same regions. 

The beetle is one of our earliest as well as latest species. 
Indications are that at least two and perhaps three generations 
are produced annually in the District of Columbia, and prob- 
ably four in the insect's more southern range. Eggs are laid 
at the base of the insect's food plant and have been observed 
by the writer to hatch in six and seven days in cool May 
weather. 

Remedies. — We cannot reach the insect, to any extent, by 
means of poisons and their use on growing corn is impractica- 
ble. Therefore, we must have recourse to farm methods. 
Injury to corn is greatest when seed is planted in bottom lands, 
and if planting is necessary in such locations it should be done 
late, in the Gulf region by the first of May, or attack may be 
so distributed that damage will be inconsequential, by dropping 
about ten grains of seed-corn in each hill. Of greater import- 
ance, however, is judicious crop rotation. Numbers of crops 
are not injured by the Southern corn root- worm, and can be 
used as alternates. Of these are cotton, buckwheat, smaller 
grains, and vegetables other than beans and cucurbits. In 
the occurrence of the beetles on cucurbits remedies advised 
against the striped cucumber beetle should be used. (See 
page 158.) On beans a spray of arsenate of lead should be 
employed. 



194 INSECTS INJURIOUS TO VEGETABLES 

The Western Corn Root-worm (Diabrotica longicornis Say.). 
— Notwithstanding the general employment of crop rotation 
as a means of preventing losses by this species, inflicted in- 
juries are reckoned by millions of dollars annually. Thus in 
1885 the damage to corn in 24 counties of Indiana was esti- 
mated at $2,000,000. Corn is the only food plant of the larva, 
but the beetles are somewhat more choice in food habits than 
the Southern species. In the experience of the writer and 
some others, they are partial to thistle blossoms, in which they 



Fig. 123.— Western corn root-worm, a, Beetle; b, larva, from side; c, leg of same; d, 
pupa. All much enlarged; c, more enlarged- (Author's illustration, U. S. Dept. Agr.) 

deeply imbed themselves, to sunflower and goldenrod, and are 
less frequently found on cucurbits. The beetles do some dam- 
age to corn by feeding on the pollen and gnawing the silk 
and tassels, thus to a certain extent preventing cross-fertiliza- 
tion and causing a partial blasting of ears. Other plants such 
as ragweed and smartweed are frequented for the sake of 
pollen. In late fall and early winter the beetles have the same 
habit as the twelve-spotted and striped cucumber beetles of 
gnawing into squash and pumpkin in the field. 

This species is evidently single-brooded. The beetles occur 
in the field, like the Southern species, until November, in open 
winters as late as the middle of December, which is, in the 
writer's opinion, proof positive that the beetles hibernate, but 



INSECTS INJURIOUS TO SWEET CORN 195 

as a rule the species passes the winter, according to Forbes, in 
the eggs which are deposited in the earth. 

The developing larvse live entirely beneath the surface, min- 
ing the fibrous roots, and seem capable of traveling from one 
root to another; pupation also takes place underground. The 
beetles of the new generation begin to issue during the latter 
part of August. 

Prevention and Remedy. — This species is more readily con- 
trolled than the Southern corn root-worm; injury can be pre- 
vented by simply following crop rotation. Since the insect 
feeds in its larval condition on corn alone, the planting of in- 
fested land to other crops leads to its starvation. It is im- 
prudent to plant corn in fields or meadows in which the beetle 
has been observed in abundance in au- 
tumn of the previous year. Another 
measure is recommended, as a general 
farm practice, the maintenance of the 
fertility of the soil by the use of manures 
and other fertilizers. Although this does 
not diminish attack, it enables the plant 
to withstand injury. 

THE CORN BILL-BUGS 

Bill-bugs, like wireworms and white- 
grubs, follow the planting of corn in sod 
and bottom land or in the immediate vi- 

. . . Fig. 124.— The calloused 

cinity of streams in which sedges, rushes corn bill-bug (Sphenopho- 
and similar wild vegetation grow rankly. ms callosus) - (Author's 

55 ^ J illustration.) 

They are an adjunct to the reclamation of 

swamp tracts and receive their name from the long "bills" 
which they bear. They are snout-beetles and related to weevils 
and curculios. Several species are troublesome in corn-growing 
regions, and were it not that they are exceptionally periodical 
they would take high rank with the important enemies of this 




I96 INSECTS INJURIOUS TO VEGETABLES 

crop. A year or two after the first attack, the beetles usually 
disappear, since only a few species live in the larval stage on 
corn. The larvae feed at the roots and in bulbs of the forms 
of vegetation that have been mentioned, which include nut-grass 
and various true grasses such as timothy. The greatest injury 
is due to the perforation of stalks of corn just at or below the 
surface when plants are only two or three inches high. The 
beetles sink their beaks deeply through the unfolded blades so 
that when these unroll little rows of both round and elongate 
longitudinal holes are left as evidence of earlier attack. As with 
injury by root-worms and some other insects which live in more 
or less concealment at or below the soil surface, close scrutiny 
is necessary in order to detect bill-bugs, and damage which is 
usually first manifested by the wilting and dying of plants and 
their stunted growth is apt to be attributed to other causes. 
The habits of these insects, in common with other snout-beetles 
when disturbed, of drawing their antennae and legs closely to 
their bodies, and of their bodies being frequently more or less 
covered with dirt, are of assistance in their concealment. A 
common injurious form is shown in figure 124. 

The Southern Corn Bill-bug (Sphenophorus maidis Chittn.) 
is one of the most pernicious bill-bugs, and a good example of 
a species that lives in its larval as well as adult stage on corn. 
It is most destructive in lowlands and occurs in the Gulf region 
and in Kansas. Of the habits of this species Dr. L. O. Howard 
says substantially: 

"Wherever the larva had reached full size, the pith of the 
stalk was completely eaten out for at least five inches. Below 
ground, even the hard, external portions of the stalk were 
eaten through, and in one instance everything except the root- 
lets had disappeared, and the stalk had fallen to the ground. In 
a great majority of instances a single larva was found in a 
stalk, but in a few cases two larvae were at work. In no case 
had an ear filled on a stalk bored by this larva. The stalk 



INSECTS INJURIOUS TO SWEET CORN I97 

was often stunted and twisted, and the lower leaves were in- 
variably brown and withered." 

From examination of numbers of stalks it is evident that eggs 
are laid in them near the soil surface, and the young -larvae 
usually work downwards. The presence of larvae in the stalks 
proper is apparently only after the roots and the pith below 
ground have been exhausted. The beetle (fig. 125, c, d) is black, 
and has the thorax marked with three raised lines. The length 
is about half an inch exclusive of the snout, which measures 
about one-sixth of an inch. The larva is of about the same 





Fig. 125.— The Southern corn bill-bug. a, Larva; b, pupa; c, beetle, from above; d, 
same from side. All slightly enlarged. (From Riley, U. S. Dept. Agr.) 

length as the beetle, nearly white, of the peculiar curved form 
shown at a, the head being a little darker and the mouth-parts 
still darker. 

The Northern Corn Bill-bug (Sphenophorus zecz Walsh) is 
somewhat restricted to the north as regards injuries. The adults 
alone injure corn, the larvae subsisting on the roots and bulbs of 
timothy and other grasses. In 1891 the writer investigated an 
invasion of this species in Chester County, Pennsylvania, where 
the beetles were attacking newly-planted corn just beneath the 
surface. As was surmised before visiting this point, a stream 
of water was running close at hand in the marshy soil where 
rank vegetation grew in profusion, including different forms 
of sedges, rushes, weeds and wild grasses, the obvious original 
starting place of the insect. The principal damage was done to 
cornfields located from fifty to one hundred feet above the creek 



igS INSECTS INJURIOUS TO VEGETABLES 

bed. In one field not a single plant had escaped attack. Ap- 
proximately 50 per cent, of the plants had been killed outright, 
and 25 per cent, of the remainder were so severely damaged as 
to necessitate replanting. In some fields a second replanting 
had been necessary. In the latter days of May the bill- 
bugs were in the height of their work of demolition, and had 
nearly ceased by the second week of June. 

The Clay-colored Bill-bug (Sphenophorus cequalis Gyll.) 1 . — 
This species (fig. 126) resembles the preceding in depredating 




Fig. 126.— Clay-colored bi8-bug. a. Beetle; b, work in rush bulb; c, larva 
(Insect Life, U. S. Dept. Agr.) 



on corn only in the adult stage, its larva developing in the bulbs 
of club rush and related plants. It is the largest of our in- 
jurious corn-feeding species of this group. 



METHODS OF CONTROL 

Injury to other crops than corn by bill-bugs is comparatively 
insignificant, and the same holds of the larvae. The beetles 
are the occasion of the greatest losses when corn is first 
planted and their amazing vitality makes it difficult to combat 
them with poisons which are practically inert. 

1 Mentioned in economic literature as Sph. ochreus Lee, 



INSECTS INJURIOUS TO SWEET CORN I99 

Bill-bug injury in general may be avoided by not planting 
corn in land already liable to be infested, such as swampy 
ground, river bottoms, or in soil in which rank grasses and 
sedges are growing. Before planting, such ground should be 
thoroughly broken up and grown to some crop which the 
beetles will not injure. Bill-bugs so far as known injure only 
corn, rice, timothy, nut-grass and other grasses, and occasionally 
smaller grain. Cotton, tobacco, buckwheat, potatoes or other 
garden vegetables, or other crops than those mentioned as 
susceptible to bill-bug attack, will serve as alternates. 

Direct remedies are possible against bill-bugs whose larvae 
also injure corn. One of these consists in plowing up and 
burning infested stubble, when the larvae are present in such 
numbers that the ruin of a crop is assured. This should be 
done late in July or early in August for most localities, 
before the insects have matured and issued from the stalks 
as adults. Some species, e. g., the Southern corn bill-bug, pass 
the winter as adults in the stubble and for these burning over 
the fields as soon after harvest as possible is indicated. In the 
case of the Northern bill-bug do not plant corn after timothy. 

The Common Stalk-borer {Papaipema nitela Gn.). — This in- 
sect enjoys the distinctive designation of the stalk-borer, but 
it has numerous other names of which are the heart-worm and 
potato stalk-borer. Although a general feeder, it is quite as 
commonly found attacking corn as other crops, hence may be 
mentioned in connection with the two species that have just been 
considered. 

The moth (fig. 127, a) is medium gray-brown or fawn color, 
and marked as shown. The growing larva (b) is peculiar in 
having the first three or four abdominal segments suffused in 
such a manner as to give it the appearance of being diseased. 
The mature larva measures about an inch and a half and has 
more or less the appearance shown at c. The abdominal seg- 
ment of the larva is shown at d, while at e is shown the female 



200 



INSECTS INJURIOUS TO VEGETABLES 



chrysalis. This stalk-borer is credited with doing injury to 
the stalks of tomato, potato, spinach, cauliflower, eggplant, pep- 
per, dahlia, aster, lily, spiraea and salvia; and to the twigs 




Fig. 127.— Common stalk-borer, a, Female moth; b, half-grown larva; c, mature larva 
in Injured stalk, d, abdominal segment of same; e, pupa. All somewhat enlarged. 
(Author's illustration, U- S. Dept. Agr.) 

of blackberry, currant, apple and peach, as well as to the stems 
and stalks of wheat and corn. 

When the borer infests the crop plants that have been 
enumerated the portions above the point of attack in the stem 
wilts and finally withers before breaking down. In the case 
of infestation to such rank-growing vegetation as ragweed 
{Ambrosia trifida), cocklebur and the like, several larvae of this, 
as well as other, species may be present without seeming harm to 
the weed's growth. In large stems the larva normally passes its 
entire existence in a single plant, but when small grains are 
attacked it deserts one for another. 



INSECTS INJURIOUS TO SWEET CORN 201 

The different species of this genus of which there are many 
seem to agree in transformation to pupae in the larval burrow, 
the last act of the larva before making its final moult being 
the construction of a large opening about one-fourth inch in 
diameter for its escape when the moth condition is attained. 
The pupal period lasts from two to four weeks and the moths 
issue sometime in September or October. 

Remedies. — In ordinary cases this stalk-borer can be held in 
check in the small vegetable garden which it has invaded by 
pulling and burning infested plants. As the moth lays her eggs 
on the stems in September, fall plowing is advisable, or raking 
up and burning all forms of vegetation, especially ragweed. 

In large fields it is difficult to combat, but its injuries may be 
prevented by care in keeping down, and by promptly destroying, 
the weeds after they are pulled or hoed out during the growing 
season. If weeds are left to dry the striped caterpillar of this 
species will desert them and enter cultivated plants. Crop rota- 
tion is advisable where this can be conveniently practiced, and 
such plants as cabbage, radish and the like, onions, beets, 
asparagus and celery are suggested as alternates. When the 
plants are sprayed with arsenicals for other insects this will 
operate to a certain extent against this stalk-borer. 

Owing to the frequency of attack on the borders of culti- 
vated fields, it might be found a measure of some value to per- 
mit the ragweed to grow at these points as lures to the in- 
sects, and destroy them before September, i. e., before the moths 
have issued to lay their eggs for another generation. Fall 
plowing should be practiced or the fields burned over late to de- 
stroy the eggs. 

The Larger Corn Stalk-borer (Diatrcea sac char alls Fab.). — 
This pernicious corn pest, although a southern insect, in a 
succession of seasons which favor its development sometimes 
works northward as far as Delaware and New Jersey, where it 
is occasionally-injurious, and westward to Kansas. It is identical 



202 



INSECTS INJURIOUS TO VEGETABLES 



with the sugar-cane borer of the South. In seasons of 
abundance a loss of 25 to 50 per cent of the crop is not un- 
usual. Sometimes a stalk contains as many as 30 or more 
holes drilled by this borer. In addition to corn and sugar-cane, 
the borer has been noticed on sorghum and gama or sesame 
grass. 

The moth or parent of this stalk-borer is extremely variable 
as regards size and markings. There is an individual variation 
from an inch to nearly an inch and a half in wing expanse. 




Fig. 128.— Larger corn stalk-borer, a, Female moth; b, wings of male; c, pupa; d, e,f, 
larvae. Near natural size. (After Howard, U. S. Dept. Agr.) 



The fore-wings are pale ochreous with fine darker longitudinal 
lines, with a discal dot and marginal ones arranged as shown 
(fig. 128, a, b) in the illustration. The larva when full grown 
measures three-fourths of an inch or a little longer. Some 
are white and some strongly marked with black or brown 
arranged in round and elongate spots. This variation is well 
shown in figures d, e, and /. 

Dr. L. O. Howard was the first person to investigate the 
habits of this insect in the United States. The moths appear 
in spring, and soon after young corn comes up lay eggs on the 
leaves near the axils, and the borers on hatching penetrate 
the stalks near the joint, tunnelling usually upward through the 
pith. The borer grows rapidly, and frequently leaves a stalk 
at one place and enters at another, making several holes in the 



INSECTS INJURIOUS TO SWEET CORN 203 

course of its lifetime. When full fed it penetrates to the outer 
surface of the stalk and makes a hole from which in due 
time it issues as a moth. Figure 129, a, shows a stalk infested 
by the first generation of borers, and b a stalk cut open to 
show the larval burrow in which the pupa is resting. The 




Fig. 129.— a, Stalk infested by first generation of borers; b, stalk cut open (redrawn) 

pupa state is assumed in Virginia from the middle of July on, 
and the moths issue ten days to two weeks later. The eggs 
for the second generation are deposited soon afterwards on 
higher grown stalks, and the larvae are mature by harvest time. 
The injury accomplished by the second generation consists 
largely in the weakening of the stalk so that it is readily blown 
down by winds, whereas damage by the earlier generation pre- 



204 INSECTS INJURIOUS TO VEGETABLES 

vents the maturing of the ears. The borers of the second gen- 
eration (most of them) pass the winter as larvae. The 
periods of this species in a given locality are tolerably regular, 
hence it follows that early corn is more frequently infested 
than later plantings, and corn planted after the first of June 
is less apt to be seriously infested. Fortunately severe cold 
spells kill off the insect from time to time in the North, and 
the writer has seen corn fields practically ruined and a year 
or two later has been unable, after hours of search, to find more 
than one or two individuals on the same farms. 

Remedies. — If planters would be more careful in methods 
of cultivation this corn stalk-borer would have no chance to 
propagate in the North. In regions infested by this insect 
corn should not be planted until after the first of June. Strip- 
ping or pulling corn for fodder, so prevalent in the South, 
and leaving the bare stalk with ear attached, is a bad practice, 
not alone on account of this, but other insects, and should 
be discontinued. Treating of the species only as a sugar-corn 
pest, it should be stated that the same remedies should be prac- 
ticed on field corn, sugar-cane and sorghum to prevent the 
insect spreading from one field to another. Butts of corn 
should not be left in the field after harvest, as they afford safe 
places for larval hibernation, but should be dragged off and 
burned as promptly as possible. 

Rotation of crops, if practiced over considerable areas, 
would greatly diminish the numbers of this pest, and if pursued 
in connection with clean farming severe losses would be averted. 
Observation has shown that the average damage to crops 
planted upon land which was in corn the previous year reached 
25 per cent, while the average to corn planted on sod land was 
only 10 per cent, even where this land was close to former 
corn land. 

The Smaller Corn Stalk-borer (Elasmo palpus lignosellus 
Zell.). — This stalk-borer was first observed depredating on corn 



INSECTS INJURIOUS TO SWEET CORN 



205 



in the Southern States not earlier than 1878, and years later 
injurious occurrences in stems of beans and peanuts were 
reported. The moth is exceedingly variable. The fore-wings 
are pale yellow or ochreous, and the outer border, toward the 
ends, consists of dark, purplish scales. The female (b) has 
fore-wings varying from reddish to nearly black and the 




Fig. 130.— Smaller corn stalk-borer, a, Male moth; b, fore-wing of dark female; bb, 
antenna of female; c, male at rest; d, larva; e, ventral segment of larva from side, 
much enlarged; /, cocoon. All except e three times natural size. (Author's illustra- 
tion, U. S. Dept. Agr.) 

hind-wings transparent, silvery fuscous. The larva (fig. 130, d) 
is half an inch or more in length when mature, and a most 
beautiful object when viewed through the lens; pale green, 
marked with nine reddish brown longitudinal stripes, arranged 
in transverse bands. Transformation takes place in a cocoon 
formed of sand or dirt (fig. 130, f). 1 

This is a tropical species, occurring from the Gulf as far 
north as North Carolina. It also inhabits Central and South 
America. 

"While chiefly injurious to young corn, destroying many 

1 A full account of this species is given in Bui. 23, Bu. Entom., U. S. Dept. 
Agr., pp. 17-22. 



206 INSECTS INJURIOUS TO VEGETABLES 

stalks and necessitating the replanting of many hills, the smaller 
stalk-bor.er works throughout the entire summer and fall, and, 
as late as October, cuts the toughened stalks of the late corn 
to such an extent that they are easily blown to the ground, and 
the ears are often rendered useless by contact with the wet 

earth. The principal work of 
the borers is done at the surface 
of the ground, although they are 
often found just above or below 
this point." 

Injury to the root stalk ex- 
tends, occasionally, to the depth 
of two inches. In attack on beans 
the larvae also work in the earth, 
holes showing where they force 
out their excrement or make their 
escape. In one case of infesta- 
tion upwards of 90 per cent, of a 
planting was destroyed. Where 
peanuts have been injured, as 
much as half a crop was de- 
stroyed, the larvae sometimes pen- 
etrating the shells of the tubers. 
When about to transform, this 
borer leaves the stalk and spins 

Fig. 131. -Cornstalk showing work of ^ oyal somew h a t flattened CO- 
smaller corn stalk-borer. Natural size. 

(After Riley, u. s. Dept. Agr.) coon, which becomes covered 

with earth or excremental pellets. 
Remedies. — As this stalk-borer hibernates in all stages — larva, 
pupa and adult — a practical remedy is difficult to find. The 
pulling up and burning of infested material as early as possible 
after the crop is removed, and rotation with some crop that 
would not be affected by this species, are desirable. The 
smaller cereals, sweet potato, cotton, cucurbits, potato, tobacco 




INSECTS INJURIOUS TO SWEET CORN 



207 



and asparagus are suggested as alternate crops. It does not 
seem possible that the insect could be reached with insecticides 
with profit. Kerosene emulsion or bisulphid of carbon, how- 
ever, should be tried. 

This brings us to the subject of the insects injurious to the 
ears. Of these the corn-ear worm is the most important. 

The Corn-ear Worm (Helio- 
this obsoleta Haw.). — The 
maturing ears of corn and 
pods of beans and cowpeas are 
often found bored full of holes 
and the seed within devoured. 
The insect most often con- 
cerned in damage of this na- 
ture is figured herewith. It is 
a well known enemy of corn, 
cotton and tomatoes, whence 
it has received the vernacular 
names corn-ear worm, boll- 
worm, and tomato fruit worm. 
It is a species of wide distribu- 
tion and destructiveness, but 
whether indigenous to this 
country or imported is not 
known. In addition to the Fi s- 132 
crops mentioned, this species 
injures tobacco, pumpkin, 

squash, melon, pepper, okra and other vegetables. Even if only 
a single hole is made in an ear of corn, the damage is apt to be 
considerable, as the remainder is likely to become more or less 
decomposed and access is afforded to other insects and to rain. 
The same is true of the injuries by this insect to other fruits, 
to tomatoes, beans, etc. 

The adult moth is ocher yellow, more or less variegated with 




Corn-ear worm (Heliothis obsoleta 
Haw.) and characteristic injury to ear of 
corn. (Quaintance, U. S. Dept Agr.) 



208 



INSECTS INJURIOUS TO VEGETABLES 



blackish markings, and arranged as in figure 132^, a. It meas- 
ures about an inch and a half across its expanded fore- wings. 
The ear worm itself varies greatly in color, different shades of 
pink, purple and green prevailing. A dark striped form is 
shown at b. 

Injury to young corn 
by the first genera- 
tion is confined largely 
to the "bud," and be- 
comes apparent as 
the ragged or shot- 
holed leaves unfold. 
It is rarely serious in 
extent. Likewise, in- 
jury by the second 
generation is compar- 
atively insignificant, 
but the third genera- 
tion, affecting roast- 
ing ears, may be the 
cause of much loss. 
Remedies. — No practical means, aside from farming methods, 
such as late fall or winter plowing, and judicious rotation of 
crops, have, as yet, been discovered for reducing injury to 
corn. The remedy which gives most promise of controlling 
this pest farther north consists in planting, where weather con- 
ditions permit, several days earlier than customary, and taking 
chances on the weather which may follow. A few days' differ- 
ence may save considerable corn. In any case, it is advisable 
to plant as early as possible, since, as a rule, the later the corn 
is planted the more injury by the ear worm. 

The Fall Army Worm (Laphygma frugiperda S. & A.). — ■ 
If it were not for its extreme periodicity of attack the fall 
army worm would rank high as a corn pest, as it affects not 




Fig. 1 32x.— Corn-ear worm, a, Moth; b, larva 
(Author's illustration, U. S. Dept. Agr.) 



INSECTS INJURIOUS TO SWEET CORN 



209 



only the foliage, but bores into the ears when they are quite 
young, destroying them utterly. The writer has seen fields 
in Virginia badly attacked in this manner, the outward appear- 
ance so closely simulating that due to the corn-ear worm as to 
deceive all who witnessed the injury. It is discussed more 
fully on page 56 on army worms. 

The Brown Fruit-chafer {Euphoria inda Linn.). — The ears 
of green corn, ripening fruits and some flowers are subject to 
the attack of the stout hairy brown beetle figured in 133. The 
length is half an inch or more. The larva (d) is a white-grub, 
with the lower moiety of the body of a dull leaden hue from 
the contents of the abdomen. Transformation^ to pupa takes 
place in a cocoon smooth within and irregular on the outer 
surface. This species occurs practically everywhere in the 
United States east of the Rocky Mountains. 




Fig- 133-— Brown fruit-chafer, a, Beetle; b, egg; c, d, larvae; e, pupa All enlarged 
(Author's illustration, U. S. Dept- Agr.) 

Injury is confined to newly transformed beetles in autumn. 
The food of the larva is manure, humus, and similar material, 
and not healthy roots, as once supposed. The beetles feed 
naturally on sap exuding from wounds in trees, and juices of 
overripe or injured fruits or other vegetable growth, and 
have an especial fondness for ears of ripening corn, particularly 
sweet corn, and even bore through the husks to the kernels 
within. The beetles devour flowers of different fruits, and 



2IO INSECTS INJURIOUS TO VEGETABLES 

attack fruit exposed for drying. The large size of these beetles 
and their habit of assembling in numbers render them at times 
an object of much apprehension. About the District of Colum- 
bia the beetles may be seen in April flying low, with a loud 
humming sound like a bumblebee. The new generation begins 
to appear toward the end of August, the date varying with 
locality and season, and after they have fed for two or three 
weeks they go into winter quarters. A single generation is 
produced in a year. 

Remedies. — Hand methods are available remedies for the 
beetles when they occur in abundance. The use of insecticides 
on ripening fruit is practically out of the question. During the 
heat of the day, particularly in bright sunlight, the beetles are 
active, but in the shade when feeding they can readily be 
captured by jarring them from the plants on which they occur 
into bags or nets. Fortunately, the species is only intermittently 
troublesome, and therefore it need not cause serious alarm. 

Cutworms and Other Caterpillars. — The fondness of cutworms 
for young corn is proverbial, and rarely is a corn field entirely 
exempt from the presence of these ancient foes of man. Sweet 
corn is particularly affected by these ravagers, but as a rule, 
owing to the later planting of corn, it does not suffer so 
great injury as plants that are reset from forcing houses, such 
as tomato, cabbage, and the like. Nearly all other field and 
garden caterpillars, including the fall army worm and garden 
webworm, with general feeding tendencies, will attack corn 
when more preferred plants are lacking. 

The corn cutworm (Noctua c-nigrum Linn.) better known 
as the spotted cutworm, is one of our commonest and most 
destructive species, and resembles the variegated cutworm 
treated on pages 53 and 54, being cosmopolitan, nearly om- 
nivorous, a climbing species, and traveling in armies like the 
army worm. The cutworm (fig. 134, b) is pale brown or gray, 
sometimes whitish, with green or olive tints, and measures 



INSECTS INJURIOUS TO SWEET CORN 



211 



fully about an inch and a half. The moth has brown fore- 
wings, tinged with reddish or purplish, and marked as figured 
(fig. 134, a). In addition to corn and cereals, this species 
affects cabbage, turnip, pea, carrot, tomato, celery, rhubarb and 
other vegetables. 

Cutworm remedies are discussed on page 54. 




Fig. 134.— Spotted cutworm, a, Moth; b. larva. Somewhat enlarged 
(Author's illustration) 

Flea-beetles. — A considerable number of flea-beetles are com- 
monly found on corn, but of these the two species mentioned 
below are more particularly attached to this crop. All species 
are most troublesome on young plants. 

The brassy flea-beetle (Chcetocnema puli- 
caria Mels.). Injury to sweet corn by flea- 
beetles is sometimes complicated by the 
presence of two species. The present is 
the more abundant of the two in most 
localities, and as it is considerably smaller, 
it is probable that it is usually the cause of 
the trouble attributed to it. It measures 
less than one-twentieth of an inch, and is 
of oval, convex form, with shining surface, 
having a faint greenish-bronze lustre. The 
legs are usually brownish testaceous, and 
the thorax bears little trace of polish (fig. 135). 




Fig. 1 35-— Brassy flea- 
beetle. For size see line 
at right. (Author's illus- 
tration, U. S. Dept. Agr.) 



212 



INSECTS INJURIOUS TO VEGETABLES 



It occurs in Pennsylvania, Maryland, Virginia, District of 
Columbia, North Carolina, Texas and Colorado. 

The toothed flea-beetle (Chcetocnema denticulata) resem- 
bles the species just figured. It is, however, much larger, 
measuring fully twice as long, or about one-tenth of an inch, 
is more robust, somewhat irregularly oval, the entire surface 
brightly bronzed and slightly brassy. 

It is distributed from New England to Florida, Texas and 
Montana, and is found even in California. 

Remedies. — These two species can be destroyed by arsenicals 
and other remedies advised in the discussion of flea-beetles 
(pages 65 and 66). 

Other Insects. — For a consideration of other insects which 
injure corn, such as wire worms and white grubs, see pages 
73 to 83. 

A species of wireworm common in the corn fields of the South 
is illustrated in its several stages in figure 135^". 





Fig. 1 3 5x.— Southern corn wireworm (Monocrepidius vespeviinus) . a b, Larva; c, beetle; 
d, pupa — about three and one-half times natural size. (Author's illustration, U. S. 
Dept. Agr.) 



CHAPTER XIII 

INSECTS INJURIOUS TO POTATO AND SIMILAR 
VEGETABLES 

Solanaceous vegetables include potato, tomato, eggplant, 
pepper and cultivated species of Physalis, one of which is 
known as husk tomato. A moderate number of insects are 
attached to these plants and most of them affect tobacco, be- 
sides weeds of the same family. 

The most important potato insect in the economic sense, is 
the Colorado potato beetle, followed by half a dozen or more 
destructive blister beetles, and less important species of the 
same group. Numerous species of cutworms select the tomato 
and potato as their particular prey and the latter plant is favored 
by several forms of flea-beetles. Among other insects which 
take their name from the potato are the potato stalk-weevil and 
potato stalk-borer, potato tuber moth and potato scab gnat. The 
two species last mentioned injure particularly the stored 
product, and several other insects attack the tubers in the 
ground. Of such are wireworms and certain cutworms, e. g., 
the variegated cutworm, when they become unusually numerous, 
and white grubs. 

All of the general feeders which have been mentioned are 
treated in introductory chapters. Some of the blister beetles, 
more particularly the striped blister beetle, are known as old- 
fashioned potato beetles. In the Southwest there are numerous 
species of these insects which affect the potato crop in that 
section. One of the potato stalk-borers is treated under the name 
of "the common stalk-borer" in the chapter on corn insects 
(page 199). 

213 



214 INSECTS INJURIOUS TO VEGETABLES 

Three species of aphides commonly occur on potato and are 
apt also to attack tomato, eggplant, and other Solanaceae. The 
same is true of mealy-bugs. The aphides include the common 
"green fly," * "black dolphin," 2 and "melon louse." 3 Some forms 
of tree-hoppers and related species, and thrips also, attack 
these plants. 

The Colorado Potato Beetle (Leptinotarsa decemlineata Say.). 
— Soon after the Civil War the Colorado potato beetle created 
quite as great consternation as the San Jose scale at the present 
time. There is perhaps no more familiar insect to those who 
live a rural life, and every country boy or girl knows its two 
active stages. It is still one of our worst pests owing to 
the fact that we must wage more or less perpetual warfare to 
suppress it. In its early days there seemed to be no check to 
its increase, but in the course of years many natural enemies 
have learned to prey upon it, until in many localities it is 
largely kept in abeyance by such agencies. It is of peculiar 
interest as being the direct cause of the use of Paris green 
upon edible plants. Fortunately, with a little knowledge of the 
habits of this insect, the use of arsenicals and the friendly 
assistance of natural enemies, the insect can now be held in 
practical subjection, otherwise it would be one of the greatest 
scourges of this country. 

This insect is so well known that a description is hardly 
necessary, but that there may be no danger of confusing it 
with blister beetles and others of similar habits, with which 
it is occasionally associated, a few words of description may be 
given. The beetle is of the robust form shown in figure 136, 
d, d, ochre yellow in color, with the wing-covers ornamented 
with ten black lines. The eggs are oval and orange colored, 
and are deposited in masses of a dozen (a, a) or more on the 
lower surface of the leaves. The larvae or "slugs" (b, b) are 

1 Rhopalosiphum dianthi Schrk. 2 Aphis rumicis L. 3 Aphis gossypii Glov. 



INSECTS INJURIOUS TO POTATO, ETC. 215 

as well known as the beetles. They are soft, slimy, red-colored, 
evil-looking creatures. 

The Colorado potato beetle was first associated with injury 
to potato in 1865, prior to which time it had fed on the sand 
bur. 1 With the advance of civilization westward and the culti- 
vation of potato in the vicinity of its native home, the insect 




Fig. 136.— Colorado potato beetle, aa, Eggs; bb, larvae; c, pupa; dd, beetles— all enlarged 
about one-fourth; e, wing-cover— much enlarged. (After Riley) 

acquired the habit of feeding on this more succulent plant. By 
1869 it had found its way to Ohio and the year following was 
very destructive throughout the Northwest, continuing its 
eastward march at an increasing rate. 

Since that time its migration eastward, northward and south- 
ward has continued. Its progress eastward was accomplished 
largely by flight, as the writer had occasion to observe when a 
resident of Cleveland in the early days of its invasion of the 
Buckeye State. With outspread wings numerous individuals 
could be seen on bright days in spring and early summer, 
being carried with the winds directly eastward. By the cen- 

l S. olanum rostratum. 



2IO INSECTS INJURIOUS TO VEGETABLES 

tennial year the Colorado potato beetle occupied an area com- 
posing more than a third of the United States. 

Beetles and larvae are destructive in nearly equal proportion. 
In its early occurrence as a pest it not only caused entire 
losses of crops, but sometimes destroyed the potato yield of 
whole counties, and large portions of some States. Indeed, 
at one time it materially affected the market price of potatoes 
by direct depredations and in discouraging farmers in the 
cultivation of this crop. At the present time growers recognize 
the fact that the control of the potato beetle is a part of the 
routine of the culture of this tuber, and that its natural enemies 
assist in a remarkable degree in reducing its numbers. The 
insect is nearly always found on its wild plants wherever they 
occur and it practically feeds on all solanaceous crops and 
weeds, including tomato, tobacco, ground cherry, thorn apple, 
and Jamestown weed, henbane (hyoscyamus), belladonna, 
petunia, and Cayenne pepper. The tender leaved varieties of 
potato are most affected, while those with less tender foliage, 
of the "Peach Blow" and "Early Rose" type, are comparatively 
immune. 

The beetle hibernates under ground and is credited with 
being double-brooded with sometimes a third partial generation, 
which hibernates in the pupal condition. The beetles appear 
early in spring, issuing soon after the first thawing of the 
ground, at this season flying during the more heated portions 
of warm days, making aerial journeys of considerable extent. 
Larvae hatch in from less than a week to a little later, accord- 
ing to the prevailing temperature, and in two or three weeks 
usually acquire maturity, when they undergo transformation to 
pupae and subsequently to beetles in cells which the larvae 
form in the earth. The insect is to be found in practically 
all stages during the summer months, and as long as there are 
suitable plants for food. A single female is capable of pro- 
ducing from five hundred to a thousand eggs. The entire life 




INSECTS INJURIOUS TO POTATO, ETC. 21? 

cycle from egg to adult may be passed in a single month, 
and the last generation of beetles issues early in autumn and 
re-enters the earth for hibernation. Fluctuation in numbers 
of the Colorado beetle is noticeable at least locally every sea- 
son, and is largely attributable to the activity of its insect ene- 
mies and to atmospheric conditions. Up- 
wards of 30 species of insects prey upon 
this beetle. One of the most important of 
these is a predaceous ground-beetle, Lebia 
grandis Hentz (fig. 137). 

Remedies. — No other methods are nec- 
essary than the free use of Paris green 
or arsenate of lead and mechanical means 
for its destruction. 

Hand-picking, if employed early in the 
season, is of great value, but where large Fi g- '37. -Lebia grandis. 
areas are planted other methods are nee- beetle. (Marx del.) 
essary. Gathering the beetles and their 

larvae in pans containing a little water on which a little kerosene 
is floating, is an effective remedy. Methods of preparing and 
applying the arsenicals are given in the chapter on insecticides. 

If the grower can secure the cooperation of his neighbors in 
the destruction of this pest, and will also kill the insects on 
wild plants, much can be done toward limiting its numbers in 
small areas. It seldom, if ever, migrates as formerly, and there 
is not so much likelihood of reinfestation from a distance. It 
is always wisdom to keep down weeds, and in the treatment of 
the present insect, if they were cut before seeding, it would 
serve a dual purpose in preventing the increase of weed as well 
as insect. The susceptibility of the "slugs" to extreme heat, 
indicates that the remedy for the asparagus beetle of brushing 
them from the plants on hot dry days will be effective. 

The Potato Flea-beetle (Epitrix cucumeris Harr.). — Much 
injury to potato is inflicted by flea-beetles which attack most 



2l8 



INSECTS INJURIOUS TO VEGETABLES 



solanaceous plants, of which they are specific enemies, riddling 
the leaves with punctures and causing them to die, thus weak- 
ening the vitality of the plants, while the larvae of some of them 
feed at the roots and do injury in this manner. The most im- 
portant of these insects are three species known respectively 
as the potato, the eggplant and the tobacco flea-beetles, their 
names indicating the plants which they most often injure. 
This potato flea-beetle (fig. 138) is the most destructive of 
this group. The name "cucumber flea-beetle" was given it by 





Fig- 138.— Potato flea-bee:le. 
Much enlarged. (Author's il- 
lustration, U. S. Dept. Agr.) 



Fig. 1 39. — Egg-plant flea-beetle. 
Greatly enlarged. (Author's il- 
lustration, U. S. Dept. Agr. ) 



Harris, who found it very destructive to cucumber, eating the 
seed leaves and destroying the plant. It is very minute, meas- 
uring only 1/16 inch in length, perfectly black, with clay- 
yellow antennae and legs, and there is a deep transverse furrow 
at the base of the thorax. This species is generally known 
from Massachusetts to Georgia, and westward to California. 

Injuries are most apparent, however, in the North. The 
larva is confined to solanaceous plants for food, and is the cause 
of "pimply" potatoes. When this trouble attracted attention 
in New York in 1894, potato buyers were on the lookout for 
potatoes so affected, offering a reduced price for them. Fre- 
quently such sold for five cents a bushel below the regular 
market price. The so-called "pimples" were accompanied by 



INSECTS INJURIOUS TO POTATO, ETC. 2IO, 

"slivers," and it was some time before it was ascertained that 
they were due to the slender white grubs of this flea-beetle. 
Eggplant, tobacco and tomato are affected less as a rule than 
potato, but the beetles also attack plants of other orders, inclu- 
ding beets, cabbage, turnip, cucumber, celery and sweet potato. 
Sometimes they do injury to potatoes by gnawing the sprouts. 
Eggs are deposited in May or June, and the life cycle is very 
like that of the tobacco flea-beetle about to be described. Larvae 
feed entirely under ground and transform to pupae there. 

Treatment. — The usual flea-beetle remedies are applicable. 
See page 65. 

The Eggplant Flea-beetle (Epitrix fuscula Cr.). — The egg- 
plant flea-beetle so nearly resembles the preceding that unless 
the two occur on the same plant they are apt to be confounded. 
It is of the same color, but considerably larger than the potato 
flea-beetle, and when closely examined it is at once seen that 
the impression at the base of the thorax is very feeble and 
that the wing-covers are more pubescent. 

This species is most abundant on eggplant, but it is common 
on potato, horse nettle and similar wild plants. In Maryland, 
Virginia and the District of Columbia it is often difficult to 
find the foliage of eggplant that has not been very profusely 
punctured by the minute holes where the beetle has been feed- 
ing. Some little time after attack these holes become browner 
on the edges, and this portion at last dries, making the holes 
much larger and giving the plants a decidedly sickly appearance. 
It even attacks eggplant in frames. This species is obviously 
southern, not extending in the East, so far as known, north 
of New Jersey. It occurs in the Gulf region and in southern 
Ohio and Illinois, and in intermediate States southward. 

Remedies. — The same as those employed against other flea- 
beetles. 

The Tobacco Flea-beetle {Epitrix parvula Fab.). — This 
species is most important as an enemy of tobacco, and like 



220 



INSECTS INJURIOUS TO VEGETABLES 



the preceding is commonest southward. Where occurring nor- 
mally it is often found in about the same abundance on potato, 
eggplant, tomato, horse-nettle, night-shade and Jamestown weed. 
The plants mentioned are sometimes damaged and its work is 
evident on these crops from Maryland and Virginia southward. 
The beetle is scarcely more than one-twentieth of an inch 
long, pale brown in color, the elytra being normally marked 

near the middle with a 
dark, transverse band of 
greater or less extent 
(fig. 140, a). The larva 
(b) is delicate, thread- 
like and white, except 
the head, which is yel- 
low. The beetle riddles 
leaves in the same man- 
ner as do other flea- 
beetles, and in its attack 
on tobacco frequently 
renders plants unfit for 

Fig. 140.— Tobacco flea-beetle, a, Beetle; b, larva; use. It IS doubtless a 
c, head of larva; d, posterier leg; e, anal segment; 

/, pupa, a, b, f, Enlarged about fifteen times; transmitter of Certain 
c, d, e, more enlarged. (Author's illustration, U. S. diseases which form a- 
Dept. Agr.) ' 

i bout the punctures made 

by the beetle in obtaining its food supply. From experiments 
by the writer it has been learned that the full life cycle may be 
passed, in extremely hot weather, in 28 days. The egg period 
in such weather is about six days, the pupa is the same, which 
affords, by deduction, a larval period of 16 days. 

Remedies are discussed on page 65, on the flea-beetles. 

The Black Blister Beetle (Epicauta pennsylvanica DeG.). — 
The farmer is quite too well acquainted with this and other 
blister beetles as unwelcome visitors to his potato patch, and 
florists know it as the "aster bug," from the severe injuries 




INSECTS INJURIOUS TO POTATO, ETC. 



221 



which it does to asters and related plants. It is uniformly 
black, without polish, and its length varies from a little more 
than a quarter to half an inch. It is 
well distributed east of the Rocky 
Mountains, and does most injury be- 
tween the Atlantic States and Texas. 
Its time of appearance is more or less 
coincident with the blossoming of the 
goldenrod, on which it is a familiar 
object, from June until October. As 
a rule it appears later than other 
species. It is one of the worst insect 
enemies of potato and beet, and is 
also destructive to carrots, beans, cab- 
bage, corn, mustard, aster, clematis Fi g- 1 41. —Black blister beetle. 

Enlarged. (Author's illustration, 




U. S. Dept. Agr.) 



and other plants. For remedies see 
page 68. 

The Potato Stalk Weevil (Trichobaris trinotata Say.). — This 
is an important insect enemy of the potato, and a common 
species almost everywhere east of the Rocky Mountains and 
south of New England. Its larva works normally in the stems 
of horse nettle, ground cherry, and jimson weed, in most fields 
where these plants are allowed to grow. 

The habit of this insect of attacking potato has been known 
since 1849. Since then injuries inflicted by it , have attracted 
considerable attention, periodically and locally, and there is 
reason to believe that it is often present and doing damage, 
though undetected, in potato fields, where the insect itself has 
never been seen. Its habit of living in the stem in its larval 
condition, and the small size of the beetles, together with 
their trick of dropping from the plants when disturbed, is 
accountable for injury so often escaping notice. 

The potato stalk weevil (fig. 142) is a small snout-beetle, 
about 1/6 inch in length. Its real color is black throughout, 



222 



INSECTS INJURIOUS TO VEGETABLES 




but its surface is covered with minute gray scales, which give 
it a nearly uniform gray appearance. The head, however, is 
black, and there are three black impressed spots at the base 
of the wing-covers. The snout is robust and rather strongly 

curved. The northern limit 
of injurious occurrence of the 
potato stalk weevil is reached 
in Pennsylvania and New 
Jersey in the East, and in Il- 
linois and Iowa in the West; 
recently, however, the species 
has been reported a pest in 
Canada. Southward the insect 
is found to Florida and Texas. 
More often perhaps than 
not, injury by this pest is at- 
tributed to drought or blight. 

Fig. 142.— Potato stalk weevil, a, Beetle; It is more conspicuous ill Sea- 
b, larva; c, pupa; d, section of potato stalk r -, ■, < i i. j 

' , . , . .. sons of prolonged drought and 

opened to show larva and pupa in situ. f is fe 

a, b, c, Five times natural size; d, natural most severe on early varieties 

size. (Author's illustration, U. S. Dept. r ™, j • • r 

of potato. 1 he undermining of 
the stalks by the larvae causes 
them to wilt, and the wilting and the dying of the leaves is the 
first outward manifestation of attack. When the insects are 
present in the field it is often stated that the plants are "blighted." 
The diseases of potato are apt also to be mistaken for the work 
of the weevil, as in both cases the leaves look as if sunburned, 
especially after the vines have been affected for some time. Not 
infrequently a field suffers from the combined effects of dry 
weather, disease, and stalk weevil. 

This insect attacks nearly all Solanacese growing within its 
natural range. The list includes, besides potato, eggplant, horse 
nettle, bull nettle, jimson weed, purple thorn apple, ground 
cherry and, it is said, cocklebur. 



INSECTS INJURIOUS TO POTATO, ETC. 223 

A single larva in a potato stalk is not sufficient to injure 
it to any extent, although it must have a weakening effect, but 
when many larvae occur destruction is complete. As many as 
5 or 6 individuals may sometimes be found in a potato stalk. 

The beetles appear, in the vicinity of the District of Colum- 
bia, in the latter portion of May, and the female deposits her 
eggs singly in small slits about one-twelfth of an inch in length 
made in the stalks of the insect's food plants, and occasionally 
in the branches. In a week or ten days the larva hatches, 
and feeds by making small channels which increase in size with 




Fig. 143.— Sigalphus curculionis. Parasite of potato stalk weevil. (After Riley) 

the growth of the insect downward toward the bases of the 
stalks. The undermining of a stalk by the tunneling of several 
larvae has the effect of impairing the vitality of the plant and 
causing the leaves to wilt and die. Upon attaining full growth 
the larva makes a cell of castings and woody fibers in which to 
transform. The beetles of the new generation appear as early 
as Jury 24. In northern localities development is slower, the 
beetles seldom appearing before August and maturing as late 
as September, and hibernation is always as a beetle. The 
knowledge of this fact is of value in the control of the species, 
as will be explained. 



224 INSECTS INJURIOUS TO VEGETABLES 

This weevil is subject to the attack of a small ' four-winged 
parasitic ichneumon fly, Sigalphus curculionis Fitch (fig. 143), 
a well-known enemy of the plum curculio, and sometimes it 
falls a prey to wireworms. 

Remedies. — The best remedy is to pull infested vines as soon 
as they wilt and show evidence of attack, and spread them out 
so that they will be exposed to the sun and will dry and thus 
prevent the escape of the insects which they contain. All stalks 
in infested fields should be burned as soon as the crop is off. 
This will greatly lessen the number of weevils for the ensuing 
years. It is also advisable to keep down all solanaceous weeds. 
The time for their destruction is in July, after they have at- 
tracted the beetles for tgg laying, or any time before the seeds 
are ripe. The use of fertilizers will often aid injured plants to 
recuperate from attack. Unfortunately, injury is not apt to be 
detected until the plants begin to die. As soon, therefore, as 
a plant shows weakness its stalk should be split open to ascertain 
the cause. Early potatoes are most subject to injury, and the 
latest varieties are practically exempt. 

The Potato Tuber Worm (Phthorimcea operculella Zell.). — 
The tuber worm is probably the most injurious insect to the 
truck industry of California, where losses to the potato crop 
have been estimated as aggregating some years 25 per cent. In 
Salinas Valley, dealers claim that at times the loss has . gone 
as high as 40,000 sacks a year. Potatoes from other sections 
have to be watched carefully to avoid "wormy" ones, as a 
very few such may infest a whole storeroom. As the potato 
is a product that is expected to retain its value for months, the 
possibility of destruction by insects while in store becomes a 
question of great seriousness, more particularly because rots 
follow the "worm," starting in its burrow and ultimately in- 
volving the entire tuber. Although the species is introduced 
and rather commonly distributed in temperate portions of the 



INSECTS INJURIOUS TO POTATO, ETC. 



225 



United States, injury to potato is nearly confined to California, 
although tobacco is attacked in the South where the insect is 
known as the tobacco leaf-miner or split-worm. It is probable 
that this insect may in time become a pest in other regions, 
though not in the colder temperature States. 

The moth (fig. 144) resembles a clothes-moth, but is darker. 
The wing expanse varies from y% to about % of an inch. The 
fore-wings are mottled with dark 
brown and black, and the hind- 
wings are narrow, with long 
fringes. Eggs are deposited on 
the leaves, and the minute worms 
(b, c) hatching from them bur- 
row into the stems and afterward 
into the potato tubers. Fre- 
quently early injury is done to 
plants in the field, but as the 
larvae grow they work, later in 
the season, farther into the stems, 
and when these harden make Fig. 144 
their way to the tubers and finish 




a&mMHffi£m 



■Potato tuber worm, a, Moth; 
b, c, larva or "worm" ; d, pupa; e, /, 
abdominal segments of larva, a-d, 
their growth there. The potato Three times natural size; e, /, more 

is subject to infestation through- ^ ged - (Insect Life ' u ' s ' Dept 
out the year, provided the tubers 

are stored in places that are not too cold for the insect's devel- 
opment. The life cycle, according to the studies of Mr. W. T. 
Clarke, may be accomplished in nine weeks, and in the winter, in 
the mild climate of California, this period is sometimes run in 
twelve weeks. When the larva is about six weeks of age it 
comes to the surface and transforms to pupa at the mouth of 
its burrow, or seeks a crack or depression in the potato when 
the tubers are stored. The usual course of the tuber worm is to 
mine beneath the outer skin of the plant, and molds and rots 
(bacterial and fungous growths) follow in its wake, the stalk 



226 INSECTS INJURIOUS TO VEGETABLES 

finally succumbing to the combined injuries of insects and dis- 
ease. Injury is three-fold to the plants above ground, and to 
the tubers in the field, and again in store. The moths oviposit 
on any part of a plant, on leaves, stems, on tubers in the hill and 
when exposed in the field and after they are stored. 

Methods of Control. — It is impossible to reach the tuber 
worms in their mines, in stalks or tubers growing in the field, 
therefore we must proceed against this pest in other ways. 
Several must be employed to insure success. First come clean 
methods of cultivation, which implies that all infested plants 
of potato and weeds of the vicinity must be destroyed, as 
such material affords a breeding place for the insect and its 
successful hibernation. Sheep and hogs can be utilized in the 
destruction of the remnants merely by turning them into the 
field. Crop rotation is desirable, and cooperation is practically 
a necessity. Where potatoes are extensively grown in a given 
region their cultivation might be discontinued for a year. Other 
plants than tomato, eggplant and tobacco would answer as 
alternates, and leguminous crops are particularly indicated, 
owing to their value as soil restorers. Careful compact hill- 
ing is an effective method in preventing infestation, especially 
to the tubers. Carelessness in digging, which consists in leav- 
ing potatoes in the field over night instead of promptly remov- 
ing them to uninfested shelter, should be avoided. 

The remedy that has been used with best results consists in 
placing infested potatoes in tight receptacles and treating them 
with bisulphid of carbon. Several treatments are sometimes 
necessary. 

The Potato-scab Gnat (Epidapus scabiei Hopk.). — Some forms 
of potato-scab are due to the attacks of minute whitish maggots 
with blackheads which feed in decayed spots in tubers as 
well as upon healthy portions. The detection of these as the 
cause of scab is due to the investigations of Dr. A. D. Hopkins, 1 

1 Special Bui. 2, West Virginia Agr. Exp. Station, 1895, pp. 97-111. 



INSECTS INJURIOUS TO POTATO, ETC. 



227 



from whose publications the accompanying account has been 
compiled. The most destructive of these is known as the potato- 
scab gnat which, in its larval or maggot form, measures about 
one-sixth of an inch in length. It is the young of a wingless 
female and winged male gnat or midge, somewhat like the 
fickle midge treated in preceding pages as an enemy to cu- 
cumber. The female deposits eggs on tubers in the cellar from 
autumn to spring. The maggots enter old scab spots or slightly 
injured places, and under favorable conditions a generation is 
developed every 20 to 25 days. Later in spring the gnats 
deposit their eggs in manure or decomposing material, on seed 




Fig. 145.— Potato scab-gnat, o, Fly; i, larva, g, egg; h, egg mass, etc Much 
enlarged. (After Hopkins) 



potatoes and growing tubers in the hill, to which they may be 
transferred on seed tubers or in decaying matter. Once within 
the tuber and the conditions remaining favorable, the potato is 
destroyed; but if the maggots are driven out by natural enemies 
or the soil becomes dry they disappear. The infested places 
show nearly the same characters as ordinary scab, for which 
malady it may be easily mistaken. The conditions most favor- 
able to the increase of this pest are moist, damp cellars, and wet 
weather during the warmer season. They cannot thrive in dry 
soil or in perfectly dry storerooms. Immense loss to potatoes 
was caused in West Virginia during 1891 and 1892, in Phila- 
delphia and probably in other sections of the country. Under 
favoring conditions for their increase, the gnats may be even 



228 INSECTS INJURIOUS TO VEGETABLES 

more destructive than the fungus, on account of their pene- 
trating while in the larval stages deep into the substance of 
the tubers, thus rendering them worthless for market. 

Methods of Control. — Preventive measures that will at the 
same time be effective against the scab fungus apply quite 
as well to the gnats and their maggots. Dr. Hopkins recom- 
mends the following measures for protection against injury: 

''Select sandy or other soils of a dry character in which a 
crop of surface growing vegetables or grain has been grown 
the previous year, and from which the refuse has been thor- 
oughly removed in order that the soil may be as free from 
vegetable matter as possible. Do not use as fertilizers animal 
manures, lime, ashes, and like substances. If a fertilizer is 
necessary, use only a ground bone, phosphate, kainit and other 
commercial fertilizers of a like character. Select smooth and 
healthy tubers for seed. . . . When the potatoes are dug, 
and before they are stored, carefully sort out all tubers showing 
the least indication of decay, as well as those which are seri- 
ously affected with scab. Do not plant the same land in pota- 
toes for at least three years after a potato crop is taken 
from it." 

Soak seed potatoes in a solution of corrosive sublimate or 
formalin according to directions furnished in the chapter on 
insecticides. In case a piece of land is especially favorable 
for the production of potatoes of excellent quality, if the pre- 
caution is taken to remove and burn all rubbish, such as potato 
tops, weeds, refuse tubers, etc., the same land may be, by 
judicious fertilizing, planted in potatoes every alternate year. 



CHAPTER XIV 

INSECTS INJURIOUS TO THE TOMATO 

In the introduction to the chapter on insects affecting potato, 
eggplant, and similar crops, it was stated that nearly all of these 
insects affect to a less extent the tomato. The species which 
will be here mentioned affect more particularly the tomato, 
and exceptionally potato and similar crops. The most im- 
portant are the tomato or tobacco worms, the common stalk- 
borer, often so abundant on tomato as to be known as the 
tomato stalk-borer, which has previously been treated (page 
199), and the tomato fruit worm, or the corn-ear worm. The 
aphides which infest potato, eggplant, etc., are likely to attack 
tomato and there are two additional species which have been 
observed on the latter. 1 Mealy-bugs, thrips, plant-bugs and 
other sucking insects also feed on it. 

The Tomato Worms. — The large green "worms" that eat 
tomato leaves are well known. There are two distinct species 
of them, closely allied, much alike in all their stages, and 
practically indentical in habits. They are called indiscriminately 
tomato or tobacco worms and "hornblowers." In the District 
of Columbia and vicinity, the two species are of nearly equal 
occurrence as regards numbers on both tomato and tobacco. 
They are the larvae of large sphinx moths. 

The tomato worm (Phlegethontius quinquemaculata Haw.). — 
The tomato or northern tobacco worm is nearly as thick as 
one's little finger, and about three and a half inches long when 
extended. The horn is larger and less curved, and usually 
dark in color, whereas the Southern species has a shorter and 

1 Rhopalosiphum solani Thos. and Nectar ophora erigeronensis Thos. 

229 



230 



INSECTS INJURIOUS TO VEGETABLES 



more curved red horn. On the sides of the body are eight 
longitudinal stripes which are met by a similar number of 
horizontal stripes, each segment forming an angle (fig. 146, b). 
The moth (a) which produces this tomato worm has a wing 
expanse of four inches or less. It is the paler form, and the 
bright orange spots on the sides of the abdomen are not so 




Fig. 



146.— Tomato worm, c, Moth; b, full-grown caterpillar; c, pupa, 
size. (After Howard, U. S. Dept. Agr.) 



Half natural 



vivid as in the Southern species and only four in number, 
whereas the Southern form has five. The hind-wings are 
marked with zigzag lines more pronounced than in the Southern 
species. The dark mahogany brown pupae of both are fre- 
quently turned out of the ground by the spade in early spring 
and later. They are the possessors of a handle-shaped process 
projecting from the head, that in the present species (fig. 146, c) 
being longer than in the Southern (fig. 148, c), indicative of the 



INSECTS INJURIOUS TO THE TOMATO 23 1 

longer or shorter proboscis of the moth of each. The pupse 
measure about two inches in length. 

The Northern species occurs throughout the United States 
and into Canada. It is also found on Jamestown weed, matri- 
mony vine and ground cherry. The moths appear from May to 
June, according to locality and season, and as far north as 
New York City two generations are annually produced. The 
writer and others have noted two generations in Maryland and 
Virginia, while as far south as Florida, according to Quain- 
tance, a third generation occurs. The moths deposit their 
eggs, usually singly, on the under surface of leaves. The eggs, 
according to Alwood's observations in Virginia, hatch in from 
four to eight days, and the caterpillars in the course of their 
growth cast their skins four times in less than a month. When 
full grown they burrow into the soil and transform to pupse. 
Both "worms" are sometimes quite dark in color, but when they 
turn nearly black they are usually infected by a bacterial dis- 
ease, which invariably kills them (fig. 147). 




Fig. 147.— Southern tobacco worm dead and shriveled from bacterial disease. Natural 
size. (After Howard, U- S. Dept. Agr.) 



Few observing persons have failed to see at sometime in 
their lives the caterpillars of these or other sphinx moths en- 
tirely covered with little white oval cocoons. These produce 
small four-winged parasites, and it is owing to the abundance 
of these and the bacterial disease that the insects are not 
more numerous than they are. 

Remedies. — The amount of damage done by tomato worms 
will vary according to the vigilance of the grower. On small 
patches the "worms" are readily seen after a little experience, 



2$2 



INSECTS INJURIOUS TO VEGETABLES 



and can be picked off by hand and destroyed, and if this is 
carefully done little apprehension may be experienced of dam- 
age. Clean culture and crop rotation are always to be prac- 
ticed and the leaving of tobacco suckers, or abandoned rem- 
nants should be avoided, as the "worms" frequently remain 
in the field until the plants are killed by frost. It should be 
unnecessary to add that the worms may be killed by spraying 
with arsenicals. Turkeys are utilized in destroying these in- 
sects in the South. 

The Southern tobacco worm (Phlegethontius sexta Joh.). — 
The differences of this species and the preceding have been 
pointed out. In brief, the moth (fig. 148, a) is darker, and 
the five orange spots on the body are larger and brighter. The 
"worm" has only seven oblique white lines on the sides, and 




Fig. 148.— Southern tobacco worm, a, Moth; b, full-grown caterpillar; c, pupa. Half 
natural size. (After Howard, U. S- Dept. Agr.) 

the tail is more curved and red. The pupa has a shorter 
proboscis. The Southern tobacco worm is distributed through 
the United States from the Atlantic to the Pacific, and from 



INSECTS INJURIOUS TO THE TOMATO 233 

Canada to the West Indies. No important differences between 
these two species have been noted as regards habits, time of 
appearance, susceptibility to diseases and to parasitic attack. 
In the writer's experience, the two species undergo their trans- 
formations throughout in about the same time. 

Remedies are the same as for the tomato worm proper previ- 
ously treated. 

The Tomato Fruit Worm (Heliothis obsoleta Haw.). — This 
insect, as most modern farmers are aware, is the same species 
as the bollworm or corn-ear worm. It has been treated from 




Fig. 149.— Tomato fruit worm boring in tomato. (After Rile/) 

the standpoint of a cotton pest in innumerable publications, and 
is considered among corn insects on page 207, but as yet we 
have discovered no direct remedy for it in its occurrence on 
tomato. It is frequently the cause of serious trouble to tomato 
growers over large areas, due to the "worms" eating into and 
destroying the green and ripening fruit. 

Remedies. — For the protection of tomatoes, it is advisable not 
to plant in proximity to corn or cotton fields or on ground 
that has been grown the previous year to these crops or to 
beans or cowpeas, all of which are favorite host plants of this 
pest; nor should land be planted with tomatoes in infested 



234 INSECTS INJURIOUS TO VEGETABLES 

regions until it has been fall or winter plowed. Although no 
reports are available of satisfactory experiments having been 
performed in spraying for this species in its occurrence on to- 
mato, it is possible that a spray of Paris green and Bordeaux 
mixture, or of either alone, might be satisfactory. It is there- 
fore suggested that three out of four plats of equal size be treat- 
ed experimentally in each of the manners described, the fourth 
plat to be left untreated, so that the effects can be noted. Spray- 
ing may be practiced up to about a week from the time of the 
fruit ripening without danger of poisoning human beings. 

Miscellaneous Insects. — Of insects most to be feared when 
the plants are first set out are cutworms of various species. The 
tomato grower is well acquainted with these pests, and no 
description of their methods is necessary here, beyond the state- 
ment that they cut off and destroy more than they eat and re- 
setting is frequently necessary. Cutworms are discussed more 
fully on pages 49 to 56. 

Flea-beetles also attack the plants soon after they are set out. 
Their injuries can be prevented by dipping the young plants 
before setting in a solution of arsenate of lead, about 1 pound 
to 50 gallons of water, or Paris green, 1 pound to 100 gallons. 
See page 65 on flea-beetle remedies. 



CHAPTER XV 

INSECTS INFESTING THE SWEET POTATO 

The sweet potato is a staple from New Jersey and Maryland 
southward. It is seldom that plants are not more or less in- 
fested by insects, and of these the tortoise beetles are con- 
spicuous because of the holes which they eat in the leaves. As 
the crop is started under glass and transplanted, it is subject to 
attack by cutworms and similar insects. There are several 
other defoliators, blister beetles, the larvae of sawflies, a hawk- 
moth and others; flea-beetles sometimes do considerable injury, 
while in the extreme South the sweet-potato root-borer is be- 
coming an important pest from its destruction of the tubers. 
In spite, however, of a considerable number of insects which 
attack this plant, it does not, on the whole, suffer very material 
injury save in restricted areas and in years when certain pests 
are abnormally abundant. The root-borer, however, threatens 
to be a permanent pest in the Gulf region. 

The Sweet-potato Root-borer (Cylas formicarius 01.) • — In- 
jury by this insect in North America was first noticed about 
1877 near New Orleans, La., when it was claimed to threaten 
the destruction of the sweet potato crop of the country, a pre- 
diction which was, happily, not verified until about 1903. 

The adult is a weevil of ant-like form except for the long 
snout which it possesses (fig. 150, a). It is small, about one- 
fourth of an inch in length, including the snout, the elytra are 
shining dark blue, the head and snout darker blue, and the 
thorax and long legs shining red. The larva (b, c) when grown 
is about one-fourth of an inch long, white, with brown head and 
darker mouth-parts. 

235 



236 



INSECTS INJURIOUS TO VEGETABLES 



This sweet-potato borer is of Oriental origin, and its native 
habitat is credited to Cochin China. It was probably in- 
troduced from the West Indies into Louisiana and Florida, and 
from the former States into Texas. The female deposits her 
eggs in the vines near the ground, and the larvae after hatch- 
ing tunnel through the tubers, and the vines die. Frequently 
tubers are so badly riddled and have such a bitter taste that 
neither fowls nor swine will eat them. The species is capable 

6" 




Fig. 150.— Sweet-potato root-borer, a. Male beetle; $ , antenna of male, enlarged; $, 
antenna of female, enlarged; b, pupa; c, larva, dorsal view; d, larva, side view. All 
enlarged. (After Howard except d, original.) 

of undergoing transformation from egg to adult in about 31 
days and hence as many as four generations might be produced 
in a year. Considerable injury has been inflicted for a num- 
ber of years in Louisiana and in Texas. 

Remedies. — Care should be exercised not to transport tubers 
from infested localities to uninfested ones. If not too badly 
damaged the tubers may be disinfected with carbon bisulphid, 1 
small tubers should be fed to hogs, and badly infested ones 
should be burned with the vines. 

The Sweet-potato Tortoise Beetles (Cassidini). — In many 
sections, particularly where sweet potato is grown largely 
for market, this crop is attacked by tortoise beetles of which 

1 See Farmers' Bvil. No. 145, U. S. Department Agriculture. 



INSECTS INFESTING THE SWEET POTATO 



^37 



half a dozen species are common. They also affect morning- 
glory; it is seldom, in fact, that the latter plants are free from 
their attacks. The most common form of injury is manifested 
by numerous more or less rounded holes eaten in the leaves, 
and this, if traced to its source, will usually be found to be due 
to the presence of the tortoise beetles. Some of these insects 
are truly wonderful. The golden tortoise beetle, known as 
"the gold bug," is one of the most beautiful creatures imaginable 
when it is resting at ease or feeding in daylight. At this time 
it has the appearance of a globule of burnished gold. If the 
beetle is disturbed this golden color disappears, and it fades 
also toward sundown and does not remain after death in dried 
specimens. The larvae which produce these beetles are also 
remarkable because of their singular habits. They are the 




Fig. 151.— Golden tortoise beetle, a, Larvse working on leaf; b, larva divested of 
"pack "; c, pupa; d, beetle, a, Natural size; b, c, d, enlarged. (After Riley) 

possessors of peculiar forked appendages which serve as recep- 
tacles for their cast-off skins and for their excrement as it is 
voided. When divested of the cast larval skins and excrement, 
the larvae are seen to be flat below, like the beetles, and convex 
above, the margins projecting into peculiar-shaped spines. 
These larvae are sometimes termed "pedlars," the fork with its 
load being designated as the pack. Beetles, as well as larvae, 
feed chiefly on the under surfaces when not exposed to direct 
sunlight. Injury is mainly to young plants, the beetles making 
their first appearance at about the time plants are reset. Soon 
after appearing the females begin laying eggs, and in about 



2 3 8 



INSECTS INJURIOUS TO VEGETABLES 



a week or a few days longer the Jarvse hatch and assist the 
beetles in their work of destruction. Indications are that all of 
these tortoise beetles are single-brooded, hibernation taking 
place in the adult stage. 

The Golden Tortoise Beetle (Coptocycla bicolor Fab.) is the 
most striking of the tortoise beetles, and well known and destruc- 
tive. In this form (fig. 151) the entire body is golden with 
exception of the borders ; that is, when the insect 
is resting on leaves exposed to the sun. If a 
specimen be captured the colors fade to a dull, 
deep orange, sometimes with a few golden spots 
remaining, and two black spots are noticed near 
the middle of the insect. The size varies from 
two-twelfths to three-twelfths of an inch. The 
larva (b) carries its "pack" directly over the 
and the excrement is arranged in a more 
or less regular three-lobed pattern. 
The Mottled Tortoise Beetle (Coptocycla guttata 
01.). — This species is about equally as common and of the same 
size as the golden tortoise beetle. It is shown in its various 
stages in figure 153. It differs in having the elytral ground color 




Fig. 152.— Golden 
tortoise beetle 
egg. Much en- back 
larged. (After 
Riley.) 





Fig. 153.— Mottled tortoise beetle, c, larva; b, pupa; c, beetle. (After Riley) 

black, extending at the shoulders on each side. Sometimes it is 
flecked with gold and at other times with yellow. The larva 
(a) is green, with a bluish shade down the back. It carries 
its excrement and cast skins in irregular broad masses, fre- 



INSECTS INFESTING THE SWEET POTATO 



239 



quently branching as in some other species. Before changing to 
pupa it removes the faeces from its fork. The pupa (b) is also 
green, with a black ring around the base of the first abdominal 
pair of spiracles. 

The Two-striped Sweet-potato Beetle (Cassida bivittata Say.) . 
— In 1869 this was stated to be the most common of the tortoise 
beetles occurring on sweet potato seeming to be confined to that 




Fig. 1 54-— Two-striped sweet-potato beetle. 7, Larvas at work on leaves; 2 % larva; 
3 pupa; 4, beetle. J, Natural size; 2, 3, 4, enlarged. (From Riley) 

plant. From the District of Columbia northward, where the 
writer has observed it, it is much less abundant than the two 
preceding, hence it is of less importance economically. The 
beetle (fig. 154, 4) is yellow and has two black stripes on the 
elytra, whence the common name. The larva (2) is dirty 
whitish or yellowish, showing a rather indistinct line along the 
back. From similar larvae on sweet potato it can be known from 
the fact that it does not use its fork for 
carrying excrement, but only as a repository 
for cast skins. This fork is usually elevated at 
an angle of about 45 , which suggests the idea of 
a handle. 

The Black-legged Tortoise Beetle (Cassida 
nigripes 01.). — From other sweet-potato tortoise 
beetles this species (figs. 155, 156) may be dis- 
tinguished by its larger size. It measures nearly 
one-third of an inch. Like the golden tortoise 
beetle, it is reddish except when in bright sunshine, and has the 
same power of assuming a golden hue, apparently at will. Its 




Fig. 155. -Black- 
legged tortoise 
beetle. (After 
Riley.) 



240 



INSECTS INJURIOUS TO VEGETABLES 



distribution extends from ocean to ocean, and it is apparently 
more abundant on the Pacific coast than eastward. 

Remedies. — The tortoise beetles which prey upon sweet 




Fig 156.— Black-legged tortoise beetle, a, Larvae, natural size; b, larva divested of 
pack of excrement; c, pupa. Both enlarged. (After Riley) 

potato are not as a rule of great economic importance. The 
remedies prescribed below for the sweet-potato flea-beetle are 
about all that are usually required. 

The Sweet-potato Flea-beetle (Chcetocnema coniinis Lee.).— 
In parts of the United States, notably in New Jersey and Mary- 
land, this insect causes considerable injury to the sweet potato 
by eating out channels along the veins on both surfaces of the 
leaves soon after the plants are set out. This gives the leaves 
the appearance of having been attacked by a leaf-miner. Soon 
after attack on young plants, the entire surface becomes seared. 
When the insect occurs in numbers leaves are destroyed and 
plants are killed outright. Attack is most severe on ground 
previously grown in sweet potato, and also follows the clear- 
ing of fields which have been allowed to grow in bindweed, one 
of the insect's natural food plants. 

* Remedy. — Plants before setting out should be dipped in a 
strong solution of arsenate of lead, and one or two sprayings 
of the leaves with arsenicals a week or two later is about all 
that is needed, because the plants, being hardy, easily recuperate 
from attack and suffer little injury other than that of de folia- 



INSECTS INFESTING THE SWEET POTATO 24I 

tion. The first application is to accomplish the destruction of 
the beetles before they deposit their eggs, and the second and 
third are to kill beetles that may come from other plants. Rota- 
tion of crops and the avoidance of planting in the vicinity of 
neglected ground that has grown up with bindweed and wild 
morning-glory are also advisable. 

The Common Sweet-potato Sawfly (Schisoccrus ebenus Nort). 
— The larvae of two species of sawflies have been observed doing 
injury to sweet potato. 
They are comparatively 
new as pests and of similar 
habits and distribution from 
New York to the Gulf and 
northward to Nebraska. 

The present is like other 
sawflies, four-winged, and 
somewhat smaller than a 
house fly, the body is black, 
and the wings infuscated 

~- a.^i ^ru ^ 1 1 Fig- \S7.—Eubadi2on schizoceri. Parasite of 

or dusky. Ihe male has 5 , ,, ,, , .,, T , T . ( , 
J sweet-potato sawfly. (After Insect Life) 

forked antennas while the 

female has shorter simple ones. Eggs are deposited in the leaf of 
sweet potato. Attack has been observed in August and Sep- 
tember in Mississippi, and a parasite (fig. 157) has been reared 
from the larva. This parasite, and a tachina fly, which also 
preys on it, no doubt hold the insect in check and prevent 
serious injury. 

The Larger Sweet-potato Sawfly (Schizocerus privatus 
Nort.). — The first record that we have of injury by the larvae 
of this sawfly was in July, 1890, when it damaged sweet potato 
in Virginia. At that time plants that were attacked produced 
no yield whatever. This sawfly is larger than the preceding, 
the wing expanse being nearly 3/5 of an inch, and both sexes 
have yellow abdomens. Other differences can be made out by 




242 



INSECTS INJURIOUS TO VEGETABLES 



comparison of the illustration of each. According to Marlatt, 
deposition of the eggs is on the under surface of the leaf, and 
by reference to figure 158, a, it will be seen that eggs are 
placed usually in parallel rows bordering the larger veins of 




Fig. 158.— Larger sweet-potato sawfly. a, Female sawfly S ■ antenna of male; b young 
larva; c, section of infested sweet-potato leaf, showing egg deposit- d same showing larva 
hatching and feeding, a, b, d, $ , Enlarged; c, natural size. (Adapted from Marlatt.) 



the leaf. Larvae are seen hatching from the pouch-like egg 
receptacles or blisters at b. 

Remedies. — Both these sawfly larvae when abundant may be 
easily controlled by the prompt application of hellebore or 
arsenicals when they make their first appearance. 

Cutworms. — Since sweet potato is cultivated in seed-beds, 
it is subject to the ravages of cutworms when set out in newly- 
plowed fields. One of these, the dark-sided cutworm (Car- 
neades messoria Harr.), appears to be particularly identified 
with attack of this nature. It is a common species, and in addi- 
tion to various garden crops seems to revel in onions. A 



INSECTS INFESTING THE SWEET POTATO 243 

more complete account, with illustrations, has been furnished 
on page 246. The variegated cutworm, in years when it in- 
dulges in uprisings, also injures sweet potato and some other 
cutworms and other caterpillars of less importance occasionally 
cause losses to this plant. 

Remedies for these insects are duly treated on page 54. 

Mealy-bugs (Dactylopius spp.). — A species of unidentified 
mealy-bug has been mentioned by Dr. J. B. Smith as destructive 
in Salem County, N. J., in 1901, to sweet-potato in forcing beds. 1 
They were found clustered at the bases of the sprouts and of 
the small leaves. It is not probable that these insects would 
survive normal outdoor conditions when plants are set out in 
spring in New Jersey, but in the Gulf region they doubtless 
would develop out-of-doors quite as well as under glass. For 
protection against mealy-bugs cellars and storerooms should be 
thoroughly whitewashed and cleaned before the seed tubers are 
stored and the temperature should be kept low while in the beds 
where the roots are forced in spring. Cleanliness should be 
observed and the roots should be inspected before putting them 
in, and such as show the mealy-bugs should be rejected and 
destroyed. 

1 Rept. Dept. Ent. N. J. Agr. Coll. Exper. Sta. for 1901 (1902), ?. 489. 



CHAPTER XVI 

INSECTS INJURIOUS TO MISCELLANEOUS 
VEGETABLE CROPS 

THE ONION AND OTHER BULB CROPS 

Bulb crops are so similar that what will attack one is apt to 
feed on the others. Six crop plants (genus Allium) are in- 
cluded in this group: the common onion, Welsh onion, shallot, 
cive, leek and garlic. Of these only the first is grown to any 
extent in North America. "The onion," some one has remarked, 
"is one of those strenuous vegetables about which one can- 
not be indifferent. One either yearns for it with a passionate 
longing or else utterly repudiates it." The same is true as re- 
gards insects, since few species are overfond of it. The leading 
species are the onion maggot and onion thrips. A few insects 
of omnivorous tendencies, however, not infrequently do much 
injury to this plant. Of such are some forms of cutworms, and 
especially the dark-sided cutworm, wireworm, and the imbri- 
cated snout-beetle. The pungent odor of the onion and its 
kind renders it unpalatable to many insects, but some resort to 
these plants in the absence of other vegetation. 

Insect injury to onion and related plants is peculiarly local 
or intermittent, and in spite of the injurious species which 
will be treated, and the immense amount of damage that they 
have done, it is no uncommon sight, but in fact the rule, to 
see fields grown to these crops year after year for long periods 
without their sustaining any material harm. Such is the case 
about the District of Columbia, where no insects what- 

244 



INSECTS INJURIOUS TO MISCELLANEOUS CROPS 245 

ever have been noticed in recent years injuriously affecting the 
onion crop. 

The Imported Onion Maggot (Pegomya cepetorum Meade). — 
This maggot injures the onion by eating into the bulbs, the 
subsequent decay of the affected portions frequently destroying 
them. It is a most important drawback to the culture of onions 
here and in Europe, from which continent it was introduced 
years ago. It is nearly related to the seed-corn, and cabbage, 
maggots treated in former pages. In the adult state it re- 
sembles, as do the others, the common house fly. The average 
size is a little larger than the flies of the two root-maggots that 
have been mentioned, the body being about 3/16-inch long and 
the wing expanse nearly 3/8-inch. The maggot itself and the 
puparium can be distinguished from those of other root-mag- 
gots only by careful comparison. 

The life history is very like that of the cabbage maggot, 
the differences being due to the different character of the 
vegetables attacked. It follows that the natural enemies which 
prey on one are liable to attack the others, and the remedial 
measures to be adopted are also much the same. 

Remedies. — For a discussion of remedies the reader is re- 
ferred to the account of the seed-corn maggot. 

The Black Onion Fly {Tritoxa flexa Wied.). — This is an 
old enemy of onion and a native 
species, recorded from the Atlantic 
coast to Illinois. The fly is about 
one-third of an inch long, black, 
with three oblique white stripes 
on each wing. The maggot itself 
is white and larger than the root- 
feeding species previously treated. Fte- 159.-Black onion fly. Three 
T . , . ,.-,.. times natural size. (After Walsh) 

It feeds on onions and cives both in 

the field and in store. General remedies are the same as for the 




246 



INSECTS INJURIOUS TO VEGETABLES 



seed-corn maggot (page 108). In addition bisulphid of car- 
bon is desirable for the treatment of stored onions. 

Cutworms (Euxoa messoria, etc.) — Onions, as has been 
stated, are not particularly favored by many insects of om- 
nivorous tendencies, but the variegated cutworm is quite de- 
structive to it and there is one 
other species, the dark-sided 
cutworm, which might well 
be called the onion cutworm, 
from the great injuries 
which it causes to this crop. 
In 1885, near Goshen, New 
York, this cutworm (shown 
in figure 160) threatened the 
extinction of the onion in- 
dustry, the annual value of 
which was estimated at half 
a million dollars. Although 
the people worked day and 
night to keep down the pest, 
the yield was reduced during that and the following year about 
one-half, or a total cash loss of about $500,000. 

Remedies. — This species can be treated in the usual manner 
for cutworms. 

The Onion Thrips. — For an account of the onion thrips see 
page 89. 

RHUBARB 

Rhubarb or pie-plant is rather unusually exempt from in- 
jurious attack by insects, a fact which is largely to be accounted 
for by the rapid and early growth of this plant, its vigor, and 
large stalks and leaves. No natural enemies appear to have 
been introduced with it, and it generally attains full market 
growth before the appearance of most insects which might 




Fig. 160.— Dark-sided cutworm (Euxoa mes 
soria). a, Cutworm; b, moth. (After Riley) 



INSECTS INJURIOUS TO MISCELLANEOUS CROPS 247 



injure it. Several species attack rhubarb, but only two or 
three appear to prefer it to other plants cultivated in this 
country. Two insects that are specially identified with rhubarb 
are the rhubarb curculio and the rhubarb flea-beetle. It is also 
quite subject to the attack of aphides. 

The other insects which infest this plant are general feeders, 
such as cutworms and some other caterpillars and a few leaf- 
feeding beetles. 

The Rhubarb Curculio (Lixus concavus Say.). — Injury by 
the above-mentioned species is accomplished by the beetles punc- 
turing the stalks for food, although 
occasionally they attack the leaves 
and seed stalks. This causes the 
plant to exude juice copiously 
which, drying, forms clear, tear- 
like drops (fig. 161). Eggs are 
often deposited in the stems, but the 
leaves do not develop, doubtless 
owing to the moisture caused by the 
beetles' punctures. The larvae breed 
exclusively in weeds, such as dock 
(Rumex), and occasionally in sun- 1 
flower (Helianthus). 

The insect under discussion is a 
large, rusty-coated curculio or 
snout-beetle, measuring from the 
tip of its long proboscis about three- 
fourths of an inch, and being of the 
form shown in figure 162, a. 

Remedies. — The use of poisons 
on rhubarb during its growing 

season is out of the question, but the beetles are so conspicu- 
ous that they can readily be seen on the leaves, and as they are 
sluggish there is no difficulty in capturing them. They should 




Fig. 161.— Section of rhubarb stalk 
showing injury by rhubarb curculio. 
(Author, U. S. Dept. Agr.) 



248 



INSECTS INJURIOUS TO VEGETABLES 



be gathered also upon nearby plants of dock, and after the 
eggs have been deposited on the dock stems these plants should 
be pulled up and burned before the development of the adults. 
The Rhubarb Flea-beetle (Psylliodes punctulata Mels.).— 
This species shows a great preference for rhubarb where ob- 
tainable over other vegetables, among which are cucumber, 
radish, and beet. It is dark, brassy green, and finely punctulated, 
with its femora, tarsi, and the basal joints of antennae pale, 




Fig. 162.— Rhubarb curculio. a. Beetle: b, egg; c, newly-hatched larva; d, full-grown 
larva; e. pupa: /, dorsal view of last abdominal segments of pupa. All about twice 
natural size. (Author's illustration, U. S. Dept. Agr.) 



obscure yellowish. Both the upper and lower surface of leaves 
are affected by the beetle gnawing through and devouring the 
pulp, leaving the skin on the opposite side entire, which be- 
comes discolored, forming yellowish brown freckles as the 
leaf grows and expands, the skin at these points becoming in 
time torn and showing holes. When the beetles occur in num- 
bers leaves are sometimes riddled by these punctures. 

Remedies. — Ordinary flea-beetle remedies are recommended. 
(See page 65.) 



INSECTS INJURIOUS TO MISCELLANEOUS CROPS 249 

LETTUCE 

Of minor truck plants, which will be considered in this chap- 
ter, lettuce appears, on account of its tender leaves and lack of 
decided flavor, the most favored by insects. It does not seem 
to have any insects specially attached to it, but there is one 
species, the lettuce earth-louse, which may fall in this category. 
At least a score of species are known to affect it occasionally. 
Among the most troublesome of these are the common cabbage 
looper and celery worm, treated in the consideration of insects 
which affect cabbage and celery respectively. Cutworms are 
not partial to lettuce, but some species, particularly the va- 
riegated cutworm, attack it; a species of thousand-legged worm 
has been recorded as being very destructive by attacking the 
outside leaves near the main stalk and four species of aphides 
or plant-lice are recorded as feeding on lettuce. 

The Lettuce Earth-louse (Rhisobius lactucce Fitch). — This 
common eastern species occurs sometimes in destructive num- 
bers at the roots of lettuce. It is oval, dull whitish, with dusky 
legs and antennae, and measures less than one-tenth of an inch. 
The entire body is coated as though dusted with a whitish 
powder. It should be treated in the same manner as the root- 
aphides to which group it belongs. 

OKRA OR GUMBO 

The insect enemies of okra are practically the same as of 
cotton, which belongs to the same botanical family. Okra, 
however, is little damaged, and the writer has for several years 
seen plantings that were not seemingly at all injured by the 
few insects which were present. One of the principal enemies 
of okra is the melon aphis, which sometimes occurs upon it in 
great numbers. The bollworm enters the pods, but evinces no 
special fondness for them. Several leafhoppers are found on 
okra, and of these is the waved sharpshooter (Oncometopia 



250 INSECTS INJURIOUS TO VEGETABLES 

[Proconia] undata Fab.). The foliage at times shows holes 
where such general feeders as the twelve-spotted cucumber 
beetle have attacked it, apparently in wantonness, while the 
plants were still young. 

SALSIFY 

The insect enemies of salsify, or vegetable oyster, were un- 
der observation by Mr. F. M. Webster some years ago. 1 He 
records the occurrence of two common species of leaf-rollers 
and three aphides on the plant, the yellow bear, or caterpillar 
of the ermine moth, and the tarnished plant-bug. There are 
other species which attack it, all general feeders, but there ap- 
pear to be few, if any, records of injurious occurrences, 

PEPPER 

Peppers were grown in the United States until 1904 without 
serious attack by insects being re- 
corded. That year a little pest known 
as the pepper weevil (Anthonornus 
eugenii Cano) attracted attention 
by its injuries to peppers of all vari- 
eties at Boerne, Texas. This species 
(fig. 163) is a relative of the notorious 
Mexican cotton-boll weevil and has 
the same origin and a similar life his- 

Fig. 163. — Pepper weevil. tory. It is a native of Mexico from 

SThSSFo&dSS which countr y ^ has been introduced 
A s r -> into Texas. 

Remedies. — Gathering and destroying the fallen pepper pods 
in which the larva feeds and the beetle develops or burying 
the infested pods by bedding high and lowering the soil are 
suggested as methods of control. Where pepper is grown in 
irrigated land this practice serves to check the insects, as the 

iSee list, Insect Life, Vol. II., page 259. 




INSECTS INJURIOUS TO MISCELLANEOUS CROPS 25 1 

decay of the pods is hastened and the larvae are thus deprived 
of a food supply. 1 

Some of the potato and tomato pests considered in earlier 
pages occasionally infest peppers, but do not as a rule do notice- 
able injury. Among these are the tomato worms, bollworm, 
white fly, and Colorado potato beetle. 

1 This species is treated under the name of Anthonomus aneotvictus Champ, 
in Bui. 54, Bur. Ent., U. S. Dept. Agr., pp. 43-48, and Bui. 63, pp. 55-58, 
by C. M. Walker and F. C. Pratt respectively. 



CHAPTER XVII 



BIBLIOGRAPHY 

■ A short list of some of the more important and readily- 
available publications on economic entomology in which the 
insects injurious to vegetable crops are treated follows. In 
compiling such a list some precedence is given to the publica- 
tions of the Federal Department of Agriculture because as a rule 
they have a wider scope than State Agricultural Experiment 
Station publications, are printed in larger editions and are ac- 
cessible to all, being for the most part free on application. Many 
of these contain bibliographical references. The list begins with 
works on general and economic entomology. 

WORKS ON GENERAL AND ECONOMIC ENTOMOLOGY 

1 841. Harris, T. W. — Insects Injurious to Vegetation. Flint ed., 
185 1. Orange Judd Co., New York. First ed., Cambridge, 
1841. 

1855. Fitch, Asa — Reports of the State Entomologist of New York. 
I.-XIV., Albany, 1855-1870. (See Lintner's First Annual 
Report, State Ent. New York, pp. 294-297.) 

1865. The Practical Entomologist. Vols. I. and II. Published 
by the Entomological Society of Philadelphia, 1865-1867. 

1868. The American Entomologist, edited by B. D. Walsh and 

C. V. Riley. Vols. I.-IIL, 1868-1880. 

1869. Riley, C. V. — Reports of the State Entomologist of Missouri. 

I.-IX. Jefferson City, 1869-1877. 
1879. Reports of the Entomologists of the U. S. Department of 

Agriculture. J. H. Comstock (1879-1880) ; C. V. Riley 

(1878-1879, 1880-1894). L. O. Howard (1894 to date). 
1882. Lintner, J. A. — Reports of the State Entomologist of New 

York, I.-XIV. Albany, i882-'97. 

1882. Treat, Mary — Injurious Insects of the Farm and Garden. 

Orange Judd Co., 1882. (A small work compiled from 
Riley's reports.) 

1883. Forbes, S. A. — Reports of the State Entomologist of Illinois, 

I.-XXIII. 1883-1905- 

1891. Weed, C. M. — Insects and Insecticides. 281 pp., 143 figs. Han- 
over, N. H., 1891. 

1895. Comstock, J. H. and Anna B — A Manual for the Study of 
Insects. 701 pp., 797 figs. Ithaca, N. Y. 
252 



BIBLIOGRAPHY 253 

1896. Smith, J. B. — Economic Entomology. 481 pp., 483 figs. Phil- 
adelphia, 1896. 
1902. Johnson, W. G.— Fumigation Methods. Orange Judd Co., 

New York. 313 pp., 83 figs. 
1902. Sanderson, E. D. — Insects Injurious to Staple Crops. New 
York. 295 pp., 162 figs. 

Bulletins of the Division and Bureau of Entomology of the U. 
S. Department of Agriculture, I-XXXIIL, o. s., 1883-1895, 1-71, 
11. s., 1896-1907. (Buls. 19, 23, 29, S3 and 43 treat of insects injurious 
to vegetables.) Insect Life, vols. I.-VIL, 1888-1897. 

Circulars, Division and Bureau Ent. U. S. Dept. Agr., 1891-1907. 
(Ore's. 10, 16, 31, 38, 39, 43, 57, 59, 60, 62, 63, 65, 80 and 87 treat 
of insects which affect vegetable crops.) 

The publications of the various state, agricultural experiment 
stations may be obtained by residents of the States where these 
documents are issued. 

GENERAL CROP PESTS 

Cutworms. Smith — Bui. 109, New Jersey Agr. Exp. Sta., pp. 3-13, 

figs. 1-3, 1895 ; Slingerland — Bui. 104, Cornell Univ. Agr. 

Exp. Sta., pp. 553-6oo, figs., 1895. 
Spotted Cutworm (Noctua c-nigrum Linn). Chittenden — Bui. 

27, n. s., Div. Ent. U. S. Dept. Agr., pp. 54-58, 1901. 
Variegated Cutworm (Peridroma saucia Hon. [Agrotis saucia]). 

Chittenden — Bui. 29, n. s., Div. Ent. U. S. Dept. Agr., 

pp. 46-64, 1901 (includes bibliography). 
Black Cutworm (Agrotis ypsilon Rott). Riley — Rept. U. S. Dept. 

Agr. f. 1884, pp. 294, 295, 1885. 
Army Worm (Heliophila unipuncta Haw. [Leucania unipuncta]). 

Howard — Circ. 4, Div. Ent. U. S. Dept. Agr., 1894; Slin- 
gerland — Bui. 133, Cornell Univ. Agr. Exp. Sta., pp. 233- 

258, 1897. 
Fall Army Worm or Grass Worm (Laphygma frugiperda S. & 

A.). Chittenden — Bui. 29, n. s., Div. Ent. U. S. Dept. Agr., 

PP- 13-45, 1901 (Bibliography). 
Wireworms. Comstock and Slingerland — Bui. S3> Cornell Univ. 

Agr. Exp. Sta., pp. 193-272, figs., 1891 ; Slingerland — Bui. 

107, Cornell Univ. Agr. Exp. Sta., pp. 37-56, 1896; Forbes — 

18th Rept. St. Ent. Ills., pp. 27-51, 1894. 
White Grubs. Forbes, S. A.— 18th Rept. St. Ent. Ills., pp. 109-145, 

1894; Bui. 44, Univ. Ills. Agr. Exp. Sta., pp. 257-281, 1896; 

Chittenden — Bui. 19, n. s., Div. Ent. U. S. Dept. Agr., pp. 

67-80, 1899. 
Grasshoppers or Locusts. Riley — Bui. 25, o. s., Div. Ent. U. S. 

Dept. Agr., pp. 1-62, figs, and pis., 1891. (Compiled from 

1st and 2nd Repts. U. S. Ent. Comm., etc.) 
Pale-striped Flea-beetle (Systena blanda Mels. [S. tmiiata Say]). 

Chittenden — Bui. 23, Div. Ent. U. S. Dept. Agr., pp. 23-30, 

1900. 



254 INSECTS INJURIOUS TO VEGETABLES 

Red Spider (Tetranychus bimaculatus Haw. [T. telarius Authors]). 
Chittenden — Bui. 27, n. s., Div. Ent, U. S. Dept. Agr., pp. 
35-42, 1901. 

ASPARAGUS 

General. Chittenden — Bui. 10, n. s., Div. Ent. U. S. Dept. Agr., 

pp. 54-62, 1898. 
Common Asparagus Beetle {Crioceris asparagi L.). Chittenden — 

Ybk. U. S. Dept. Agr. f. 1896 (1897), PP- 341-349 5 Bui. 66, 

Bu. Ent., pp. 6-9, 1907 
Twelve-spotted Asparagus Beetle {Crioceris 12-punctata 01.). 

Chittenden— Ybk. U. S. Dept. Agr. f. 1896 (1897), pp. 

349-352; Bui. 66, Bu. Ent., pp. 9, 10, 1907. 
Asparagus Miner {Agromyza simplex Loew.). L. c, pp. 1-5, figs. 1 

and 2, 1907. 



BEANS AND PEAS 

General. Chittenden— Ybk. U. S. Dept. Agr. 1898 (1899), pp. 233- 
280, figs. 

Bean Leaf-beetle {Cerotoma trifurcata Forst. [C. caminea Fab.]) 
Chittenden — Bui. 23, n. s., Div. Ent. U. S. Dept. Agr., pp 
30, 31, 1900. 

Pea Aphis {Nectarophora destructor Johns. [Nectarophora pisi]) 
Chittenden — Bui. 23, n. s., Div. Ent, U. S. Dept. Agr., pp 
33-37, hg- 9, 1900. 

Bean Leaf -roller {Eudamus proteus Linn.). Chittenden — Bui 
33, n. s., Div. Ent. U. S. Dept. Agr., pp. 92-96, fig. 20, 1902, 

Lima-bean Stem-borer {Monoptilota nubilella Hulst). Chitten- 
den — Bui. 23, n. s., Div. Ent. U. S. Dept. Agr., pp. 9-17, 
1900. 

Smaller Corn Stalk-borer (Elasmo palpus lignosellus Zell.). Chit- 
tenden— Bui. 23, n. s., Div. Ent. U. S. Dept. Agr., pp. 17- 
22, 1900. 



BEETS AND SPINACH 



General. Forbes and Hart — Bui 60, Ills. Agr. Exp. Sta., pp. 397- 
532, figs. 97, pis. I.-IX., 1900. (A monographic account 
with bibliography) ; Chittenden — Bui. 43, Div. Ent. U. S. 
Dept. Agr., pp. 1-71, figs., 1903. (Short accounts of princi- 
pal insect enemies.) 

Leaf -miner {Pegomya vicina Lint.). Sirrine — 14th Annual Rept. 
Board of Control, N. Y. Agr. Exp. Sta., pp. 625-633, PI. IV.. 
1896. 



BIBLIOGRAPHY 255 

Larger Beet Leaf -beetle (Monoxia puncticollis Say. [Galeruca 

maritima]). Chittenden — Bui. 18, n. s., Div. Ent. U. S. 

Dept. Agr., p. 95, 1898. 
Beet Aphis (Pemphigus beta? Doane). Doane— Bui. 42, Wash. 

State Agr. Exp. Sta., 14 pp., 4 figs., 1900. 
Beet Army Worm (Laphygma exigua Hbn.). Chittenden— Bui. 

33, n. s., Div. Ent. U. S. Dept. Agr., pp. 37-46, fig., 1902. 
Beet Webworm (Loxostege sticticalis Guen.). Gillette — 13th 

Ann. Rept. Colo. Agr. Exp. Sta., pp. 128-130, 1900 (1901) ; 

Bui. 98, Agr. Exp. Sta. Colo., pp. 3-12, pis. I. and II., 1905. 

CABBAGE AND OTHER COLE CROPS 

Cabbage Maggot (Pegomya [Phorbia] brassicce Bouche). Chit- 
tenden — Circ. 63, Bu. Ent., U. S. Dept. Agr., pp. 3-6, figs., 
1906; Slingerland— Bui. 78, Cornell Univ. Agr. Exp. Sta., 
pp. 481-577, 1894; Smith — Bui. 200, N. J. Agr. Exp. Sta., pp. 
1-27, 13 figs., 1907. 

Imported Cabbage Worm (Pontia rapes Linn.). Chittenden — 
Circ. 60, Bu. Ent., U. S. Dept. Agr., 8 pp., 6 figs., April, 
1905. 

Cross-striped Cabbage Worm (Evergestis [Pionea] rimosalis 
Guen.). Chittenden — Bui. 33, n. s., Div. Ent., U. S. Dept. 
Agr., pp. 54-59, 1902. 

Cabbage Looper (Autographa brassicce Riley [Plusia brassier]). 
Chittenden — Bui. 33, n. s., Div. Ent., U. S. Dept. Agr., pp. 
60-69, 1902. 

Imported Cabbage Webworm (Hellula undalis Fab.). Chitten- 
den — Bui. 19, n. s., Div. Ent., U. S. Dept. Agr., pp. 51-57, 
1899. 

CUCUMBER, MELON AND RELATED PLANTS 

General. Quaintance — Bui. 45, Ga. Agr. Exp. Sta., pp. 25-50, figs., 
1899; Smith — Bui. 94, N. J. Agr. Coll. Exp. Sta., pp. 3-40, 
1893. 

Striped Cucumber Beetle (Diabrotica vittata Fab.). Chitten- 
den — Bui. 19, n. s., Div. Ent. U. S. Dept. Agr., pp. 48-51, 
1899; Circ. 31, Div. Ent. U. S. Dept. Agr., 1898. 

Twelve-spotted Cucumber Beetle (Diabrotica duodecimpunctata 
Oliv.). See Corn root-worms. 

Squash Ladybird (Epilachna borealis Fab.). Chittenden — Bui. 
19, n. s., Div. Ent. U. S. Dept. Agr., pp. 11-20, 1899. (In- 
cludes bibliography). 

Melon Aphis (Aphis gossypii Glov. [Aphis cucutneris Forbes]). 
Chittenden — Circ. 80, Bu. Ent. U. S. Dept. Agr., 16 pp., 6 
figs., 1906. 

Squash Bug (Anasa tristis DeG.). Chittenden — Circ. 39, Div. 
Ent. U. S. Dept. Agr., 1899; Bui. 19, n. s., Div. Ent., pp. 20- 
28, 189 



256 INSECTS INJURIOUS TO VEGETABLES 

Squash-vine Borer (Melittia satyriniformis Hbn. [Algeria cucur- 

bitce and Melittia ceto]). Chittenden — Bui. 19, n. s., Div. 

Ent. U. S. Dept. Agr., pp. 34~40> 1899; Circ. 38, Div. Ent. 

U. S. Dept. Agr., 1899. 
Pickle Worm (Diaphania nitidalis Cram. [Eudioptis and Margaro- 

nia nitidalis]). Chittenden — Bui. 19, n. s., Div. Ent. U. S. 

Dept Agr., pp. 40-42, 1899; Lintner — nth Rept. N. Y. St. 

Ent, pp. 126-133, 1896; Quaintance — Bui. 54, Ga. Agr. 

Exp. Sta., pp. 73-91, figs., 1901 (including bibliography). 
Melon Caterpillar (Diaphania hyalinata Linn.). Chittenden — 

Bui. 19, n. s., Div. Ent. U. S. Dept. Agr., pp. 42-44, 1899; 

Quaintance — Bui. 45, Ga. Agr. Exp. Sta., pp. 42-45, 1899. 

CELERY, CARROT, PARSLEY AND PARSNIP 

Celery Looper (Autographa simplex Guen. [Plusia simplex]). 

Chittenden — Bui. 33, n. s., Div. Ent. U. S. Dept. Agr., 

PP. 73, 74, 1902. 
Greenhouse Leaf-tyer (Phlyctcenia ferrugalis Hubn. [P. rubigahs 

Guen.]). Chittenden — Bui. 27, n. s,, Div. Ent. U. S. Dept. 

Agr., pp. 7-26, 1901 (including bibliography). 
Celery Caterpillar (Papilio polyxenes Fab. [P. asterias]). Davis — . 

Bui. 102, Mich. Agr. Exp. Sta., pp. 21-24, 1893. (For mono- 
graphic treatment see works of Scudder and Edwards on 

Butterflies.) 
Carrot Rust-fly (Psila roses Fab.). Chittenden — Bui. 33, n. s., 

Div. Ent. U. S. Dept. Agr., pp. 26-32, 1902. 
Carrot Beetle (Ligyrus gibbosus DeG.). L. c, U. S. Dept. Agr. s 

PP- 32-37, 1902. 
Parsnip Webworm (Depressaria heracliana DeG.). Riley — Insect 

Life, v. 1., pp. 94-98, 1888. 
Parsnip Leaf-miner (Acidia fratria Loew. [Trypeta fratria]). 

Coquillett — Insect Life, v. VII., pp. 383, 384. 
Little Negro Bug (Corimelcena pulicaria Germ.). Davis — Bui. 

102, Mich. Agr. Exp. Sta., pp. 13-18, 1893. 

SWEET CORN 

General. Forbes— 23rd Rept. St. Ent. Ills., pp. 1-273, figs., pis., 

1905 (includes bibliography). 
Seed-corn Maggot (Pegomya fnsciceps Zett. [Phorbia fusciceps, 

Anthomyia zece, etc.]). Chittenden — Bui. 33, n. s., Div. 

Ent. U. S. Dept. Agr., pp. 84-92, 1902 ; Circ. 63, Bu. Ent. U. 

S. Dept. Agr., pp. 1-3, fig., 1906. 
Corn Root-worms (Diabrotica longicomis Say. [D. 12-punctata 

01.]). Chittenden— Circ. 59, Bu. Ent. U. S. Dept. Agr., 

8 pp., 3 figs., 1905. 
Corn Bill-bugs. General. Forbes— 16th Rept. St. Ent., Ills., pp. 58- 

74, 1890; Bui. 79, Ills., Agr. Exp. Sta., 27 pp., 1902. 



BIBLIOGRAPHY 



257 



Southern Corn Bill-bug (Sphenophorus maidis Chttn. [Sph. robus- 
tus Authors]). Forbes — L. c. ; Riley — Rept. Comm. Agr. 
1881-2, pp. 138-142, 1883. 

Clay-colored Bill-bug (Sphenophorus cequalis Linn.). — Treated as 
Sph. ochreus Lee, by Forbes, 1. c. 

Northern Corn Bill-bug (Sphenophorus zees Walsh). — Generally 
called by authors 5". sculptilis Uhl., 1. c. 

Larger Corn Stalk-borer (Diatrcea saccharalis Zell.). Howard — 
Circ. 16, Div. Ent. U. S. Dept. Agr., pp. 1-3, 3 figs., 1896. 

Smaller Corn Stalk-borer (Elasmopalpus lignosellus Zell). Chit- 
tenden — Bui. 23, n. s., Div. Ent., U. S. Dept. Agr., pp. 17- 
22, 1900. 

Corn-ear Worm; Cotton Bollworm (Heliothis obsoleta Fab. [arm- 
iger Hbn.]). Quaintance — Farmers' Bui. 191, 1904; 
Quaintance and Brues — Bui. 50, Bu. Ent. U. S. Dept. Agr., 
pp. 1-155, figs, and pis., 1905 (includes bibliography). 

POTATO, EGGPLANT AND RELATED PLANTS 

General. Riley — Potato Pests, Orange Judd Co., N. Y., pp. 1-108, 

figs. 48, 1876. 
Colorado Potato Beetle (Leptinotarsa decemlineata Say. [Doryph- 

ora 10-lineata]) . Chittenden — Circ. 87, Bu. Ent. U. S. 

Dept. Agr., 15 pp., 6 figs., 1907. 
Potato-tuber Worm or Tobacco Split-worm (Phthorimcea oper- 

culella Zell. [Lita and Gelechia solanella]). Riley and 

Howard — Insect Life, v. IV., pp. 239-242, 1892; Howard — ■ 

Farmers' Bui. 120, U. S. Dept. Agr., pp. 19-22, 1900; 

Clarke — Bui. 135, Cal. Agr. Exp. Sta., 29 pp., 7 figs., 1901. 
Potato-stalk Weevil (Trichobaris trinotata Say.). Chittenden — 

Bui. S3, n. s., Div. Ent, U. S. Dept. Agr., pp. 9-19, 1902. 
Tobacco Flea-beetle (Epitrix parvula Fab.) Chittenden — Bui. 

19, n. s., Div. Ent., U. S. Dept. Agr., pp. 85-87, 1899. 
Potato or Cucumber Flea-beetle (Epitrix cucumeris Harr.). 

Chittenden — Bui. 19, n. s., Div. Ent, U. S. Dept. Agr., pp. 

89, 90, 1899. 

TOMATO 

Northern Tobacco Worm or Tomato Worm (Phlegethontius 
quinquemaculata Haw. [Protoparce celeus]). Howard — 
Farmers' Bui. 120, U. S. Dept. Agr., pp. 10-14, 1900. 

Southern Tobacco Worm or Hornblower (Phlegethontius sexta 
Joh. [Protoparce Carolina']). Howard — L. c, ; Alwood, 
Bui. 17, n .s., Div. Ent. U. S. Dept. Agr., pp. 72-74, 1898. 

Common Stalk-borer (Papaipema nitela Guen. [Gortyna nitela]). 
Smith — Rept. Ent. Dept. N. J. Agr. Coll. Exp. Sta. f. 1905 
(1906), pp. 584-587. 

Greenhouse White Fly (Aleyrodes vaporariorum Westw.). Mor- 
rill — Circ. 57, Bu. Ent. U. S. Dept. Agr., pp. 1-9, fig., 1905. 



258 INSECTS INJURIOUS TO VEGETABLES 

SWEET POTATO 

General. Sanderson— Sweet Potato Insects, Bui. 59, Md. Agr. 

Exp. Sta., 1900. 
Sweet-potato Root-borer (Cylas formicarius Fab.). Conradi — 

Bui. 93, Texas Agr. Exp. Sta., pp. 3-16, figs., 1907. 
Larger Sweet-potato Sawfly (Schizocerus privatus Nort.). Mar- 

latt— Insect Life v. V., pp. 24-27, fig. 6, 1892. 
Sweet-potato Flea-beetle (Chcetocnema conilnis Cr.). Smith — 

13th Rept. N. J. Agr. Exp. Sta., pp. 472-475, 1892. 
Mottled Tortoise Beetle (Coptocycla signifera Hbst. [C. guttata]). 

Sanderson — L. c. 
Golden Tortoise Beetle (Coptocycla bicolor Fab. [C. aurichalcea]) . 

— L. c. 

ONION 

Imported Onion Maggot (Pegomya ceptorum Meade [Anthomyia 
and Phorbia ceparum Bouche]). Chittenden — Circ. 63. 
Bu. Ent. U. S. Dept. Agr., pp. 6, 7, 1906; Smith and Dick- 
erson — Bui. 200,»N. J. Agr. Exp. Sta., 27 pp., 13 figs., 1907, 

Onion Thrips (Thrips tabaci Lind.). Pergande — Insect Life, v, 
VII., pp. 392-395. 



RHUBARB 

Rhubarb Curculio (Lixus concavus Say.). Chittenden — Bui. 23, 
n. s., Div. Ent. U. S. Dept. Agr., pp. 61-69, 1900. 



INSECTICIDES 

1902. Hinds, W. E. — Carbon Bisulphid as an Insecticide. Farmers' 

Bui. 145, 28 pp. 
1902-04. Haywood, J. K. — Reports on Analyses of Insecticides. Buls. 
68, 76 and 82, Bu. Chem., U. S. Dept. of Agr. and Farmers' 
Bui. 146, 16 pp. 

1903. Marlatt, C. L. — Important Insecticides. Farmers' Bui. 127, IL 

S. Dept. Agr., 46 pp., 6 figs. 



INDEX 



PAGE 

Acidia fratria 184, 185 

Agriotes mancus 80 

Agrotis ypsilon 52, 53 

Aleyrodes vaporariorum 175 

Alfalfa worm xiv 

Anasa tristis . •■ 161 — 164 

Anthonomus arneotinctus 251 

eugenii 250 

Apanteles glomeratus ..15, 137, 138 
Aphides ......10, 83—85, 127—130 

Aphis brassicce 151 — 153 

gossypii 165—168, 214 

lions 11 

maidiradicis 189, 190 

rumicis 214 

Anachnida, defined 4 

Army worm, fall ...56, 59, 208, 209 

Arsenate of lead 32 

Arsenicals 30—34, 65, 137, 138 

harmless 33, 34 

Arsenic, white 33 

Arsenite of copper 32 

lime 33 

Asparagus beetle, common . .93 — 96 

work, figured x 

twelve-spotted 96, 97 

insects injuring 93 — 97 

Autographa brassicce ....7, 140, 142 

Bait for insects 54, 55 

Barrel spray pumps 45 

Bean cutworm 113 

ladybird 109, 110 

leaf-beetle 110, 111 

leaf-roller 112 

weevil, common 102 — 104 

four-spotted 106 

Beans and peas, insects in- 
juring 100—119 

Beet aphides 129, 130 

army worm 125 

beetle, Western 123 

insects injurious to ..120 — 130 

leaf-beetle, larger 122, 123 

webworm 125, 126 

Beetles, defined 6 

Bill-bugs, corn 195 — 199 

Birds, beneficial 14 

Bisulphid of carbon. 42, 102, 133, 167 

Blister beetles 66—69, 124 

Bollworm, figured xi 

see also Heliothis 113 

Bordeaux mixture ....29, 55, 56, 65 

Bran-mash 55, 138 

Bruchus chinensis 104 — 106 

obtectus 102—104 

pisorum 100 — 102 

quadrimaculatus . 106 



PAGE 

Brushing methods .. ..27, 116, 117) 

Bucket pumps 45 

"Bud-worm" of corn 191 

"Bugging" 27 

Buhach, or pyrethrum 40 

Burning over fields and waste 

lands 18 

Butterflies, defined 7 

Cabbage aphis ....151 — 153 

butterfly, Southern 139 

flea-beetle, Western ..147, 148 

insects injuring 131 — 154 

looper 7, 140 — 142 

maggot . 131 — 135 

webworm, imported ..142 — 144 

worm, cross-striped 140 

imported 136 — 139 

Cantharis nuttalli 118, 119 

Carbolic-acid emulsion .37, 108, 132 
Carbon bisulphid, see Bisulphid 
of carbon 

Cameades messoria 242, 243 

Carrot beetle 185 — 187 

rust fly 176—179 

Carrots, insects injurious to 184 — 188 

Cassida bivittata 239 

nigripes 239, 240 

Caterpillars, miscellaneous ..60 — 62 

Celatoria diabroticce 157 

Celery caterpillar 179, 180 

insects injurious to ..176 — 186 

leaf-tyer 180—182 

looper ..._ 182, 183 

Centipedes, briefly defined 5 

Cerotoma trifurcata 110, 111 

Chcetocnema confinis 240, 241 

denticulata 212 

pulicaria 211 

Chinch bugi false 150, 151 

Chrysomelidae 62 — 66 

Clean farming ....22, 158, 159, 167 

Click beetles 80, 81 

Cole crop insects 131 — 154 

Coleoptera (beetles), defined 6 

Collecting insects, see also hand- 
picking 27 

Compsomyia^macellaria, figured ...8 
Control of insects, natural ele- 
ments in 11 — 15 

Cooperation in control of in- 
sects 23 — 25 

Copidosoma truncatella 142 

Copper arsenite 32 

Coptocycla bicolor 238 

guttata .••;.... 238, 239 

Corimelcena pulicaria 183 

259 



26o 



INDEX 



PAGE 

Corn bill-bugs 195 — 199 

cutworm 210, 211 

ear worm 113, 207, 208 

insects injuring 189 — 212 

root-aphis 189, 190 

root-worms 191 — 195 

stalk-borer, larger 201 — 204 

stalk-borer, smaller ..204—207 

Corrosive sublimate 37, 38 

Covering, cloth 27, 28 

Cowpea weevil 104 — 106 

Crioceris asparagi 93 — 96 

12-punctata 96, 97 

Crop pests, general 49 — 91 

rotation, see Rotation 

Crustacea, briefly defined 4 

Cucumber beetle, striped ..156 — 159 
twelve-spotted ..159, 191 
—193, 218 

flea-beetle 218 

insects injuring 155 

Cultivation methods ..21, 132, 133, 

138, 139 
Cultural methods, see Farming 
methods 

Currant leaf hopper 85 

Cutworm, corn 210, 211 

dark-sided 246 

spotted 210, 211 

variegated 53, 54 

Cutworms ..49—59, 113, 124, 145, 
210, 211, 242, 243, 246 

Cylas formicarius 235, 236 

Depressaria heracliana ....187, 188 
Diabrotica longicornis ....194, 195 

12-punctata 159, 191—193 

figured xiii 

vittata 156 — 159 

Diacrisia virginica 60 

Diamond-back moth 144, 145 

Diaphania hyalinata 173 — 175 

nitidalis 1 71 — 1 73 

Diatrcea saccharalis 201 — 204 

Diedrocephala versuta . . 117 

Diptera, defined 8 

Disking 21 

Disonycha xanthomel&na ..121, 122 

Diversified agriculture 20 

Domestic animals, destroying 

insects 79 

"Drill-worm" 191 

Driving insects 68, 159 

Eggplant flea-beetle 219 

Elasmopalpus lignosellus ..204 — 207 

Empoasca Aavescens 85 

Entomology, value of knowledge 

of 1-^3 

Epicauta letnniscata 67, 68 

maculata 68 

marginata 124 

pennsylvanica 220, 221 

vittata 67 

Epidapus scabiei 226 — 228 

Epilachna borealis 160, 161 

corrupta 109, 110 

Epitrix cucumeris 217 — 219 

fuscula 219 

parvula ..219, 220 



PAGE 

Eubadizon schizoceri, figured ..241 

Eudamus proteus 112 

Euphoria inda 209, 210 

Euschistus variolarius, figured ..10 

Eutettix tenella 128 

Euthrips tritici, figured 10 

Euxoa messoria 246 

Evergestis rimosalis 140 

Fall army worm 56 — 59 

harrowing 170 

plowing 21, 78, 82 

Farming methods, to prevent 

insect injury ..16 — 25, 65, 66 

Feltia annexa 53 

Fertilizers, danger from organic. 108 

mineral 108 

"Fire bug" 149 

Fish-oil soap 38 

Flea-beetles ..63—66, 121, 122, 146 
—149, 211, 212 

Flies defined . 8 

Formalin 38 

Fruit-chafer, brown 209, 210 

Garden flea-hopper 118 

webworm 61, 62 

Gas lime 34, 35 

Granulated cutworm 53 

Grasshoppers 69 — 73, 127 

Greasy cutworm 52 

Ground beetle, fiery, figured ....12 

Gumbo, insects injuring 249 

Hair-streak, gray 113, 114 

Halticini 63—66 

Halticus uhleri 118 

Hand-picking ..27, 56, 108, 109, 132 
Harlequin cabbage bug ....148 — 150 
Heliophila (Leucania) unipuncta. 59 

Heliothis obsoleta 113, 207, 208, 

233 234 

Hellebore' 35, 108, 135 

Hellula undalis . 142 — 144 

Hemiptera, defined 9 

Heteroptera, defined 9 

Hexapoda (insects) defined 5 

Hippodamia convergens, figured ..6 

Homoptera, defined 9 

Honey-dew 84, 85 

Hopper-dozers 27 

Hot water, as insecticide. .38, 39, 138 

Hymenoptera, defined 8 

Insecticide apparatus 43 — 47 

Insecticides 30 — 39, 78 

applying 47 

proprietary 42, 43 

Insects, injurious, determina- 
tion of xii 

injury, manifestations of x 

life history of 2 

classification 3 — 6 

natural elements in control 

of 11—15 

predaceous 12 

useful 14 

Inspection, farm 22, 23 

Tune beetles 73 — 79 

Kerosene and sand 108 

emulsion ..16, 37, 65, 116, 138, 
167, 178 



INDEX 



26l 



PAGE 

Knapsack sprayer 44 

Lace-wing fly, figured 1 1 

Lachnosterna arcuata 76 

cribrosa 77 

farcta 77 

fusca 76 

Ladybird, convergent, figured ....6 

spotted 95 

Ladybirds 13 

Laphygma exigua 125 

frugiperda ..56—59, 208, 209 

Leaf-beetles 62—66, 121—124 

-hoppers .85—87, 117, 127, 128 

-miners 127, 153, 154 

Lebia grandis 13, 217 

Lepidoptera, defined 7 

Leptinotarsa decemlineata .214 — 217 

Lettuce earth-louse 249 

insects injurious to ..248, 249 

Ligyrus gibbosus 185 — 187 

Lime 34 

Lixus concavus 247 

Locusts 69 — 73 

London purple 32 

Loxostege similalis 61, 62 

sticticalis 125, 126 

Lygus pratensis 87, 88 

Macrobasis unicolor 119 

Mancasellus brachyurus, figured ..4 

May beetles 73 — 79 

Mealy-bugs 243 

Mechanical methods of destroy- 
ing insects 26 — 29 

Megilla maculata 95 

Melanoplus differential's 71 

femur-rubrum 70 

spretus 9, 70, 71 

Melanotus communis 80, 81 

Melittia satyriniformis ....168 — 171 

Meloidce 66 — 69 

Melon aphis 85, 165 — 168 

caterpillar 173—175 

insects injuring 155 — 175 

Millipedes, briefly defined 5 

Milyas cinctus, figured 12 

Mites, defined 4 

Monocrepidius vespertinus, fig- 
ured 212 

Monoxia consputa 123 

puncticollis 122, 123 

Moths, defined - 7 

Murgantia histrionica ....148 — 150 

Myriopoda, defined 5 

Natural elements in control of 

insects 11 — 15 

Nectarophora cucurbitce . . . 165 

destructor 114 — 117 

erigeronensis 229 

Negro bug, little 183 

Neuroptera, defined 10 

Nicotine extracts and powders . .41 

Noctua _ clandestina 51 

c-nigrum 210, 211 

Nozzles, spraying 47 

Nysius^ angustatus 150, 151 

minuius 151 

Ogdoconta cinereola 113 



PAGE 

Okra, insects injurious to 249 

Oncometopia undata 249 

Onion fly, black 245 

insects injuring 244 — 246 

maggot, imported 245 

thrips 89, 90 

Orthoptera, defined 9 

Papaipema nitela 199 — 201 

Papilio polyxenes 179, 180 

Parasites, useful 14 

Paris green 30 — 32 

Parsley, insects injuring ..184 — 188 

Parsnip leaf-miner 184, 185 

webworm 187, 188 

Parsnips, insects injuring .184 — 188 

Pea aphis 114 — 117 

moth ill, 112 

weevil 100 — 102 

Peas, insects injuring ....100 — 119 

Pegomya brassicce 131 — 135 

cepetorum 245 

fusciceps 106—109, 135 

Pemphigus beta 129 

Pepper, insects injuring 250 

Peridroma saucia 53, 54 

Phoedon ceruginosa 147 

Phlegethontius quinquemaculata 

229—232 

sexta 232, 233 

Phlyctcenia ferrugalis 180 — 182 

Phthorimaa operculella ...224 — 226 

Phyllotreta pusilla 147, 148 

vittata 146, 147 

Physopoda, defined 10 

Pickle worm 171 

Pie-plant, insects injuring. .246 — 248 

Plant-bug, brown, figured 10 

tarnished, figured 11 

Plant-bugs ..10, 83, 87, 88, 117, 

118, 127, 128, 148—151 
Planting to avoid insect injury 

17, 158 
Plant-lice, see Aphis and Aphides 

Plusia simplex 182, 183 

Plutella maculipennis 144, 145 

Podisus maculiventris 95 

Poisoned baits 54, 83 

Poisons, contact 36 — 39 

_ stomach 30, 35 

Polistes bellicosus, figured 5 

Pontia napi 139, 140 

protodice 139 

rapes 136 — 139 

Potato beetle, Colorado ..214 — 217 

flea-beetle 217—219 

insects injuring 213 — 228 

scab gnat 226 

stalk weevil 221—224 

tuber worm 224 — 226 

Potherb butterfly 139, 140 

Preventives ■ ... 16, 78, 79 

Proprietary insecticides 42, 43 

Protection of plants 55 

Pruning, as insect remedy 28 

Psilarosce 176—179 

Psylliodes punctulata 248 

Pteromalus puparum. 14, 15, 137, 138 
Pyrethrum..39, 40, 65, 138, 159, 167, 



262 



INDEX 



PAGE 

Red-legged locust 70 

Red spider . . 91 

Repellents 28, 29 

Rhizobius lactucce 249 

Rhopalosiphum dianthi ....151, 214 

solani 229 

Rhubarb curculio 247 

flea-beetle 248 

insects injuring 246 — 248 

Rocky mountain locust ..9, 70, 71 

Root-maggots . „ 131 — 135 

Rotation, crop 19, 79, 82, 83 

Salsify, insects injuring 250 

Scaptomyza Haveola 153, 154 

Scheele's green 32 

Schizocerns ebenus 241 

privatus 241, 242 

Screw-worm, figured 8 

Seed-corn maggot . . . 106 — 109, 135 

Semasia nigricana Ill, 112 

Sharpshooter, waved 249 

Sigalphus curculionis 223 

Soap, insecticide 38, 65, 167 

Soldier-bug, bordered 12, 95 

spined 95 

Sowing, late 178 

Sphenophorus aqualis 198 

callosus 195 

maidis 196, 197 

zea> 197, 198 

Spinach flea-beetle 121, 122 

insects injuring 120 — 130 

Sprayer, knapsack 44 

Spraying 36, 37, 43 — 47 

Spraying apparatus 43 — 47 

Spring plowing 1 70 

Squash bug 161 — 164 

ladybird 160, 161 

-vine borer 158 — 171 

Stalk-borer, common 199 — 201 

Stiretrus anchor ago 95 

Suffocation, insecticides which 

kill by 39 — 42 

Sugar-beet leaf-hopper 128 

Sulphur 41, 42 



Sweet corn, insects injuring 

189—212 
Sweet-potato beetle, two-striped. 239 

flea-beetle 240, 241 

insects affecting 235 — 243 

root-borer 235, 236 

sawflies 241, 242 

tortoise beetles 236 — 238 

Syrphus ribesii, figured 13 

Systena . blanda 63, 64 

tceniata 64, 65 

Tarnished plant-bug 1, 87, 88 

Tarred paper cards 133 — 135 

Tetranychus bimaculatus 91 

Thecla melinus 113, 114 

Thousand-legged worms 5 

Thrips 10, 89—91 

tabaci 89, 90 

tritici 90, 91 

Tiphia inornata 78 

Tobacco, as insecticide 40 

flea-beetle 219, 220 

Tomato fruit worm 233, 234 

insects injurious to ...229 — 234 

worms 229 — 233 

Tortoise beetles 237 — 240 

Trap crops .138, 139, 158, 159, 170 

Trapping insects 28 

Trichobaris trinotata 221 — 224 

Trichopoda pennipes 163, 164 

Tritoxa flexa 245 

Turnip flea-beetle, striped .146, 147 
leaf-miner, imported ..153, 154 

Tychea brevicornis 130 

Variegated cutworm it 53, 54 

Vermorel nozzle 47 

Water-cress leaf-beetle 147 

sowbug, illustrated 4 

Whale-oil soap 38 

Wheat thrips 90, 91 

wireworm 80 

White fly 175 

White grubs 73—79, 130 

Wireworms 79 — 83, 130, 212 

W-marked cutworm 51 

Yellow bear 60 



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covered are the fruit market, fruit picking, sorting and pack- 
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fruit trade, fruit package laws, commission dealers and dealing, 
cold storage, etc., etc. No progressive. fruit grower can afford 
to be without this most valuable book. Illustrated. 232 pages. 
5x7 inches. Cloth , . $1.00 

Systematic Pomology 

By F. A. Waugh, professor of horticulture and landscape 
gardening in the Massachusetts agricultural college, formerly 
of the university of Vermont. This is the first book in the 
English language which has ever made the attempt at a com- 
plete and comprehensive treatment of systematic pomology. 
It presents clearly and in detail the whole method by which 
fruits are studied. The book is suitably illustrated. 288 pages. 
5x7 inches. Cloth , $1.00 



Feeding Farm Animals 

By Professor Thomas Shaw. This book is intended alike 
for the student and the farmer. The author has succeeded in 
giving in regular and orderly sequence, and in language so 
simple that a child can understand it, the principles that govern 
the science and practice of feeding farm animals. Professor 
Shaw is certainly to be congratulated on the successful manner 
in which he has accomplished a most difficult task. His book 
is unquestionably the most practical work which has appeared 
on the subject of feeding farm animals. Illustrated. $ l / 2 x 8 
inches. Upward of 500 pages. Cloth $2.00 



Profitable Dairying 

By C. L. Peck. A practical guide to successful dairy man- 
agement. The treatment of the entire subject is thoroughly 
practical, being principally a description of the methods prac- 
ticed by the author. A specially valuable part of this book 
consists of a minute description of the far-famed model dairy 
farm of Rev. J. D. Detrich, near Philadelphia, Pa. On this 
farm of fifteen acres, which twenty years ago could not main- 
tain one horse and two cows, there are now kept twenty-seven 
dairy cattle, in addition to two horses. All the roughage, 
litter, bedding, etc., necessary for these animals are grown on 
these fifteen acres, more than most farmers could accomplish 
on one hundred acres. Illustrated. 5x7 inches. 200 pages. 
Cloth $0.75 

Practical Dairy Bacteriology 

By Dr. H. W. Conn, of Wesleyan University. A complete 
exposition of important facts concerning the relation of bacteria 
to various problems related to milk. A book for the class- 
room, laboratory, factory and farm. Equally useful to the 
teacher, student, factory man and practical dairyman. Fully 
illustrated with 83 original pictures. 340 pages. Cloth. 



Modern Methods of Testing Milk and Milk 
Products 

By L. L. VanSlyke. , This is a clear and concise discussion 
of the approved methods of testing milk and milk products. 
All the questions involved in the various methods of testing 
milk and cream are handled with rare skill and yet in so plain 
a manner that they can be fully understood by all. The book 
should be in the hands of every dairyman, teacher or student. 
Illustrated. 214 pages. 5x7 inches $0.75 



Rural School Agriculture 

By Charles W. Davis. A book intended for the use of 
both teachers and pupils. Its aim is to enlist the interest of 
the boys of the farm and awaken in their minds the fact that 
the problems of the farm are great enough to command all 
the brain power they can summon. The book is a manual 
of exercises covering many phases of agriculture, and it may 
be used with any text-book of agriculture, or without a text- 
book. The exercises will enable the student to think, and to 
work out the scientific principles underlying some of the most 
important agricultural operations. The author feels that in the 
teaching of agriculture in the rural schools, the laboratory phase 
is almost entirely neglected. If an experiment helps the pupil to 
think, or makes his conceptions clearer, it fills a useful purpose, 
and eventually prepares for successful work upon the farm. 
The successful farmer of the future must be an experimenter 
in a small way. Following many of the exercises are a number 
of questions which prepare the way for further research work. 
The material needed for performing the experiments'is simple, 
and can be devised by the teacher and pupils, or brought from 
the homes. Illustrated. 300 pages. Cloth. 5x7 inches. $1.00 

Agriculture Through the Laboratory and School 
Garden 

By C. R. Jackson and Mrs. L. S. Daugherty. As its name 
implies, this book gives explicit directions for actual work in 
the laboratory and the school garden, through which agri- 
cultural principles may be taught. The author's aim has been 
to present actual experimental work in every phase of the 
subject possible, and to state the directions for such work so 
that the student can perform it independently of the teacher, 
and to state them in such a way that the results will not be 
suggested by these directions. One must perform the experi- 
ment to ascertain the result. It embodies in the text a com- 
prehensive, practical, scientific, yet simple discussion of such 
facts as are necessary to the understanding of many of the 
agricultural principles involved in every-day life. The book, 
although primarily intended for use in schools, is equally 
valuable to any one desiring to obtain in an easy and pleasing 
manner a general knowledge of elementary agriculture. Fully 
illustrated. 5^ x 8 inches. 462 pages. Cloth. Net . $1.50 

Soil Physics Laboratory Guide 

By W. G. Stevenson and I. O. Schaub. A carefully out- 
lined series of experiments in soil physics. A portion of the 
experiments outlined in this guide have been used quite gen- 
erally in recent years. The exercises (of which there are 40) 
are listed in a logical order with reference to their relation 
to each other and the skill required on the part of the student. 
Illustrated. About 100 pages. 5x7 inches. Cloth. . $0.50 



Farmer's Cyclopedia 
of Agriculture 3n jg 

y/ Compendium of Agricultural Sciefice and Praclice 
on Farm, Orchard and Garden Crops, and the 
Feeding and Diseases of Farm Animals : ; • ; 

*By EARLEY VERNON WILCOX, Ph.D 
and CLARENCE BEAMAN SMITH, M.S 

Associate Editors in the Office of Experiment Stations, United States 
Department of Agriculture 



This is a new, practical, and complete pres- 
entation of the whole subject of agricul- 
=S==« ture in its broadest sense. It is designed 
W^M for the use of agriculturists who de- 
sire up-to-date, reliable information on 
all matters pertaining to crops and stock, but 
more particularly for the actual farmer. The 
volume contains 

Detailed directions for the culture of every 

important field, orchard, and garden crop 

grown in America, together with descriptions of 
their chief insect pests and fungous diseases, and 
remedies for their control. It contains an ac- 
count of modern methods in feeding and handling 
all farm stock, including poultry. The diseases 
which affect different farm animals and poultry 
are described, and the most recent remedies sug- 
gested for controlling them. 

Every bit of this vast mass of new and useful 
information is authoritative, practical, and easily 
found, and no effort has been spared to include 
all desirable details. There are between 6,000 
and 7,000 topics covered in these references, and 
it contains 700 royal 8vo pages and nearly 500 
suberb half-tone and other original illustrations, 
making the most perfect Cyclopedia of Agricul- 
ture ever attempted. 

Handsomely bound in cloth, $3.50; half nhoroccc 
{-Very sumptuous), £4-.50. postpaid 



ORANGE JUDD COMPANY, < *1LSrU5«Jft" 



OCT 11 »w» 

/OBI II 100 



